Image display

ABSTRACT

The present invention was achieved in order to provide an image display whereby one can extremely easily know the current position of one&#39;s own and also grasp the actual situation around the current position, and with which the user gets highly satisfied, having a display device to display a photo picture v 1  on a prescribed reduced scale prepared based on photo data on a scale s 1  read from a storage device in which photo data of two or more types on different scales to one area is stored, and a display switching device to conduct display switching to a photo picture v 2  on another reduced scale prepared based on photo data on another scale s 2  different from the scale s 1  with a user&#39;s command.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an image display and, more particularly, to an image display, which is adopted specifically in a navigation system, using real image data corresponding to images such as satellite photographs or air photographs of the surface of the earth.

[0003] 2. Description of the Relevant Art

[0004]FIG. 34 is a block diagram schematically showing the principal part of a navigation system in which a conventional image display is adopted. A speed sensor 2 for acquiring the distance traveled by computation from the vehicle speed, and a gyro sensor 3 for acquiring the direction in which the vehicle is headed are connected to a microcomputer 10, which concludes the position of one's car based on the computed distance traveled and the direction headed (self-contained navigation).

[0005] A GPS receiver 4, which receives GPS signals from satellites through an antenna 5, is connected to the microcomputer 10, which concludes the position of one's car based on the GPS signals (GPS navigation).

[0006] A DVD drive 6, which can capture electronic map data and the like from a DVD-ROM 7 (a storage device such as a CD-ROM is also allowed) in which electronic map data and the like are stored, is connected to the microcomputer 10, which displays a map picture wherein one's car position is precisely shown on a display panel 9 b with matching the concluded car position with the electronic map data (conducting so-called map-matching). Here, the electronic map data can be also stored in a DVD-RAM which enables a map to be updated or an HDD (hard disk).

[0007] Switch signals output from a joystick 8 a or button switches 8 b arranged on a remote control 8, or switch signals output from button switches 9 a arranged on a monitor 9 are input to the microcomputer 10, wherein the processing corresponding to these switch signals is conducted. For example, when capturing information about a travel goal from these switches, the microcomputer 10 finds an optimum route from one's car position to the goal and displays that as a guidance route with a map picture on the display panel 9 b.

[0008] Thus in the navigation system, a map picture is displayed on the display panel 9 b, and a goal entered by a user, a guidance route to the goal, a one's car position mark corresponding to the current position of one's car, a past driving trail of one's car and the like are overlaid for display on the map. The navigation system has an excellent function that by seeing this display panel 9 b sequentially, the user can obtain course information and reach the goal in accordance with the course information.

[0009] However, in the navigation system in which the above conventional image display is adopted, since a map image to be displayed is prepared using map data, it is difficult to know the current position of one's own through the map image, or grasp the actual situation around the one's current position.

[0010] That is because it is difficult to express the vertical relation between multilevel crossing roads or the like using the map image, and because there are actually a large number of roads, buildings and the like which are not shown on the map image.

[0011] As one of methods for solving such problem, an invention has been disclosed, wherein the current position of one's own is displayed on an air photo image prepared from air photo data (Japanese Kokai No. 05-113343). As an advantage in using the air photo image, buildings and the like to be landmarks become very noticeable, so that it becomes easier to know the one's current position, and it can be also made easier to grasp the actual situation around the one's current position.

[0012] However, a navigation system with which the user gets sufficiently satisfied could not be realized simply by displaying air photo pictures.

[0013] In addition, it is not true that in any case, an air photo image prepared using air photo data makes it easier to know the one's current position and also makes it easier to grasp the situation around the one's current position, compared with a map image prepared using map data. There are cases where the map image makes it easier to know the one's current position, rather than the air photo image.

[0014] For those reasons, it appears that as the next generation of navigation systems, those in which both air photo images and map images are used, neither systems in which only air photo images are used, nor conventional systems in which only map images are used, as a matter of course, will be mainstream. Therefore, the proper use of both real images such as air photo images and map images, which have different features from each other, will be important in the future.

SUMMARY OF THE INVENTION

[0015] The present invention was accomplished in order to solve the above problem, and it is an object of the present invention to provide an image display, which is adopted specifically in a navigation system, properly using both displays of real images such as air photo images and map images prepared with map data, resulting in higher satisfaction given to a user.

[0016] In order to achieve the above object, an image display (1) according to the present invention is characterized by being an image display which has a first photo picture preparing device to prepare a photo picture on a prescribed reduced scale, based on photo data read from a first photo data storage device in which photo data showing the surface of the earth is stored, and a first photo picture display device to display a photo picture on the prescribed reduced scale which is prepared by the first photo picture preparing device, comprising a second photo picture preparing device to prepare a photo picture on another reduced scale different from the prescribed reduced scale based on the photo data, and a first display switching device to conduct display switching to a photo picture on the another reduced scale which is prepared by the second photo picture preparing device with a user's command to switch the reduced scale, wherein the first and second photo picture preparing devices prepare the photo pictures without enlargement.

[0017] An image display (2) according to the present invention is characterized by being an image display which has a third photo picture preparing device to prepare a photo picture on a prescribed reduced scale, based on photo data on a prescribed scale read from a second photo data storage device in which photo data of two or more types on different scales to one area is stored, and a second photo picture display device to display a photo picture on the prescribed reduced scale which is prepared by the third photo picture preparing device, comprising a fourth photo picture preparing device to prepare a photo picture on another reduced scale different from the prescribed reduced scale, based on photo data on another scale different from the prescribed scale read from the second photo data storage device, and a second display switching device to conduct display switching to a photo picture on the another reduced scale which is prepared by the fourth photo picture preparing device with a user's command to switch the reduced scale.

[0018] Using an image display wherein the reduced scale of pictures to be displayed cannot be changed, for example, when the reduction ratio is large (resulting in a detailed display), a large-scale facility such as a theme park sometimes cannot be shown within a display screen, so that the overall situation thereof cannot be known. On the other hand, when the reduction ratio is small (resulting in a wide-area display), the situation of the facility sometimes cannot be known in detail, leading to a stress on the user.

[0019] Using the above image display (1) or (2), when a command to switch the reduced scale is given by the user, display switching from a photo picture (such as a satellite photograph or an air photograph) on a prescribed reduced scale to a photo picture on another reduced scale different from the prescribed reduced scale is conducted, resulting in a resolution of the above stress on the user.

[0020] Using the above image display (1), these photo pictures are prepared without enlargement. Therefore, for example, in a case where photo data on a scale of 2 m per pixel is stored in the first photo data storage device, a photo picture on a scale of 1 m per pixel, being enlarged compared with that on the scale of 2 m per pixel, is not prepared. As a result, blurred photo pictures are never displayed, so that only sharp pictures can be provided to the user.

[0021] And since photo data has a considerably large amount of data, compared with map data, it takes much time to read photo data from a storage device or process images. Therefore, it is difficult to conduct scaling of pictures in a short period of time like in a case of utilizing map data.

[0022] Using the above image display (2), since two or more photo pictures on different reduced scales are prepared based on photo data of two or more types on different scales to one area (such as photo data on a scale of 1 m per pixel and photo data on a scale of 2 m per pixel), the scaling of pictures is not required, leading to realization of speedy display switching.

[0023] An image display (3) according to the present invention is characterized by being an image display which has a first map picture preparing device to prepare a map picture based on map data read from a map data storage device in which map data is stored, and a first map picture display device to display a map picture which is prepared by the first map picture preparing device, comprising a fifth photo picture preparing device to prepare a photo picture showing the periphery of the current position of one's own, based on photo data regarding the periphery of the one's current position read based on the one's current position information from a third photo data storage device in which photo data showing the surface of the earth covering limited areas is stored, a first one's position judging device to judge whether the one is within the areas based on the one's current position information, and a third photo picture display device to display a photo picture showing the periphery of the one's current position which is prepared by the fifth photo picture preparing device, when the first one's position judging device judges the one to be within the areas.

[0024] An image display (4) according to the present invention is characterized by being an image display which has a first map picture preparing device to prepare a map picture based on map data read from a map data storage device in which map data is stored, and a first map picture display device to display a map picture which is prepared by the first map picture preparing device, comprising a fifth photo picture preparing device to prepare a photo picture showing the periphery of the current position of one's own, based on photo data regarding the periphery of the one's current position read based on the one's current position information from a third photo data storage device in which photo data showing the surface of the earth covering limited areas is stored, a first one's position judging device to judge whether the one is within the areas based on the one's current position information, and a fourth photo picture display device to display a photo picture showing the periphery of the one's current position which is prepared by the fifth photo picture preparing device, with a user's command to display the photo picture while the one has been judged to be within the areas by the first one's position judging device.

[0025] An image display (5) according to the present invention is characterized by being an image display which has a first map picture preparing device to prepare a map picture based on map data read from a map data storage device in which map data is stored, and a first map picture display device to display a map picture which is prepared by the first map picture preparing device, comprising a fifth photo picture preparing device to prepare a photo picture showing the periphery of the current position of one's own, based on photo data regarding the periphery of the one's current position read based on the one's current position information from a third photo data storage device in which photo data showing the surface of the earth covering limited areas is stored, a first one's position judging device to judge whether the one is within the areas based on the one's current position information, a first switch forming device to form a command switch for giving a command to display the photo picture, when the first one's position judging device judges the one to be within the areas, and a fifth photo picture display device to display a photo picture showing the periphery of the one's current position which is prepared by the fifth photo picture preparing device, when the command switch is turned on by a user.

[0026] Since photo data has a considerably large amount of data, compared with map data, it is extremely hard to record photo data covering all over the country on a scale of 1 m per pixel, for example, in a recording medium such as a DVD-ROM. Therefore, it is considered that photo data covering limited areas such as the major cities is recorded, while map data covering all over the country is recorded.

[0027] Using the above image display (3), when going into the areas (e.g. the major cities such as Tokyo and Osaka) whose photo data is recorded, a photo picture showing the periphery of the current position of one's own (e.g. one's car) is automatically displayed, so that the user can easily grasp the situation around the one's current position.

[0028] And using the above image display (4) or (5), the photo picture is displayed with a command to display the photo picture by the user while the one is within the areas, so that the user can allow the photo picture to be displayed according to the user's desire.

[0029] Furthermore, using the above image display (5), a command switch for giving a command to display the photo picture is formed only when the one is within the areas. For example, in the case of the command switch being a touch button which is turned on by touching the screen, a touch button appears on the screen, so that the user can easily recognize that the user is within the areas wherein the photo picture can be seen.

[0030] An image display (6) according to the present invention is characterized by comprising a sixth photo picture preparing device to prepare photo pictures showing prescribed spots, based on photo data regarding the prescribed spots existing on a guidance route or around the guidance route read based on the guidance route information from a first photo data storage device in which photo data showing the surface of the earth is stored, and a sixth photo picture display device to display a photo picture showing the prescribed spot which is prepared by the sixth photo picture preparing device.

[0031] As for the above image display (6), for example, when a second switch forming device to form command switches for giving commands to display the photo pictures so as to correspond to each spot is mounted and a user turns on the command switch formed by the second switch forming device, a photo picture showing the spot corresponding to the command switch which was turned on is displayed by the sixth photo picture display device.

[0032] By the way, in map pictures displayed by a conventional navigation system, the expression has limits, so that it is sometimes impossible to provide sufficient information concerning places having plural levels such as interchanges or places having complicated structures.

[0033] Using the above image display (6), photo pictures showing prescribed spots (such as interchanges, service areas and tourist spots) existing on a guidance route or around the guidance route are displayed. Therefore, since the places which are difficult to express in a map picture can be displayed with the photo pictures, the user can easily grasp the places. In addition, by showing tourist spots and the like having good points worth seeing with the photo pictures, the drive can be made more enjoyable.

[0034] Furthermore, for example, by forming command switches for giving commands to display the photo pictures so as to correspond to each spot, the user can easily select a spot the user desires.

[0035] An image display (7) according to the present invention is characterized by comprising a seventh photo picture preparing device to prepare a photo picture based on photo data read from a first photo data storage device in which photo data showing the surface of the earth is stored, a seventh photo picture display device to display a photo picture which is prepared by the seventh photo picture preparing device, and a detailed information providing device to provide detailed information regarding spots to a user, based on detailed data related to the spots existing within the area shown in the photo picture read from a detailed data storage device in which detailed data related to prescribed spots is stored.

[0036] As for the above image display (7), for example, when a third switch forming device to form command switches for giving commands to provide the detailed information so as to correspond to each spot is mounted and a user turns on the command switch formed by the third switch forming device, detailed information related to the spot corresponding to the command switch which was turned on is provided to the user by the detailed information providing device.

[0037] Using the above image display (7), detailed information (such as information regarding admission fees and business days) related to spots (such as places of amusement and restaurants) existing within the area shown in a photo picture is provided to the user. Therefore, an image display unit which can give the user higher satisfaction can be realized.

[0038] Furthermore, for example, by forming command switches for giving commands to provide the detailed information so as to correspond to each spot, the user can easily select a spot the user desires.

[0039] An image display (8) according to the present invention is characterized by comprising an eighth photo picture preparing device to prepare a photo picture showing the periphery of a goal, based on photo data regarding the periphery of the goal read based on the goal position information from a first photo data storage device in which photo data showing the surface of the earth is stored, and an eighth photo picture display device to display the photo picture showing the periphery of the goal prepared by the eighth photo picture preparing device.

[0040] An image display (9) according to the present invention is characterized by the eighth photo picture display device, which displays the photo picture showing the periphery of the goal when the goal is selected by a user in the above image display (8).

[0041] An image display (10) according to the present invention is characterized by comprising a second one's position judging device to judge whether one reaches close to the goal based on the one's current position information and the goal position information, wherein the eighth photo picture display device displays the photo picture showing the periphery of the goal when the second one's position judging device judges the one to have reached close to the goal in the above image display (8).

[0042] Using any of the above image displays (8)-(10), since a photo picture showing the periphery of a goal is shown, the user can obtain a variety of information related to the goal such as information about whether the goal is in the midtown area, information about whether the road is wide or narrow, information about whether the area is densely built-up or not, or information about whether there are places of amusement or parking spaces.

[0043] Using the above image display (9), since a photo picture showing the periphery of the goal is displayed when the goal is selected, the user can grasp the situation of the periphery of the goal in advance. Using the above image display (10), since a photo picture showing the periphery of the goal is displayed when one reaches close to the goal, the user can grasp the situation of the periphery of the goal just before the arrival at the goal.

[0044] An image display (11) according to the present invention is characterized by being an image display which has a first map picture preparing device to prepare a map picture based on map data read from a map data storage device in which map data is stored, and a first map picture display device to display a map picture which is prepared by the first map picture preparing device, comprising a seventh photo picture preparing device to prepare a photo picture based on photo data read from a first photo data storage device in which photo data showing the surface of the earth is stored, and a third display switching device to conduct display switching from the map picture to the photo picture and/or from the photo picture to the map picture with matching the area shown by the map picture with the area shown by the photo picture.

[0045] As for the above image display (11), the third display switching device conducts the display switching, for example, with picture processing of a fade-in and/or a fade-out (giving various kinds of display effects).

[0046] Using the above image display (11), display switching from a map picture to a photo picture and/or vice versa is conducted with matching the area the map picture shows with the area the photo picture shows, so that the switching of these displays can be performed without making the user feel unnatural.

[0047] Furthermore, for example, if the display switching is conducted with image processing such as a fade-in and/or a fade-out (e.g. the transmittance of the screen display is variable in the 100% to 0% range), visually excellent display switching can be achieved.

[0048] An image display (12) according to the present invention is characterized by being an image display which has a ninth photo picture preparing device to prepare a photo picture showing the periphery of the one's current position, based on photo data related to the periphery of the one's current position read based on the one's current position information from a first photo data storage device in which photo data showing the surface of the earth is stored, a ninth photo picture display device to display a photo picture showing the periphery of the one's current position which is prepared by the ninth photo picture preparing device, and a first current position display device to show the one's current position on the photo picture based on the one's current position information, comprising a second map picture preparing device to prepare a map picture based on map data read from a map data storage device in which map data is stored, and a fourth display switching device to conduct step-by-step display switching from the photo picture to the map picture according to the one's travel, by making the display area of the photo picture smaller, while making the display area of the map picture larger based on the one's current position information.

[0049] In the above image display (12), for example, it is desired that the fourth display switching device should conduct the display switching with matching the area shown by the photo picture with the area shown by the map picture.

[0050] By the way, photo data has a considerably large amount of data, compared with map data, so that it sometimes takes much time to read photo data from a storage device or process images. Therefore, it is difficult, for example, to update the picture according to one's travel with a current position mark of the one's own fixed on the display, like in the case of using map data.

[0051] In order to solve this problem, while the photo picture is fixed on the display, the one's current position mark may be moved on the photo picture. However, the photo picture is not updated according to the one's travel, so that the one's current position mark will go out of the photo picture (or display).

[0052] Using the above image display (12), the display area of a photo picture is made smaller while the display area of a map picture is made larger. Since the display switching from the photo picture to the map picture is gradually conducted according to one's travel, visually excellent display switching can be achieved. And by conducting the display switching so that the one's current position mark comes onto the map picture before the one's current position mark goes out of the photo picture (display), the above problem can be also solved.

[0053] Furthermore, display switching can be conducted without making the user feel unnatural, if the display switching is conducted with matching the area shown by the photo picture with the area shown by the map picture.

[0054] An image display (13) according to the present invention is characterized by comprising a tenth photo picture preparing device to prepare a photo picture, based on photo data read based on a predetermined condition from a fourth photo data storage device in which photo data taken in two or more different states to one area is stored, and a tenth photo picture display device to display a photo picture which is prepared by the tenth photo picture preparing device.

[0055] Using the above image display (13), a photo picture which is prepared based on photo data read based on a predetermined condition (such as a photo taken in winter) from the fourth photo data storage device in which photo data taken in two or more different states to one area (such as by seasons or by time periods) is stored is displayed. For example, it is possible to display a photo picture prepared based on photo data taken in winter in the case of December, so that an image display unit expressing a sense of the seasons can be realized.

[0056] An image display (14) according to the present invention is characterized by being an image display which has a first map picture preparing device to prepare a map picture based on map data read from a map data storage device in which map data is stored, and a first map picture display device to display a map picture which is prepared by the first map picture preparing device, comprising a seventh photo picture preparing device to prepare a photo picture based on photo data read from a first photo data storage device in which photo data showing the surface of the earth is stored, and a multi-screen display device to display a map picture which is prepared by the first map picture preparing device and a photo picture which is prepared by the seventh photo picture preparing device on the same display screen.

[0057] Using the above image display (14), a map picture (a picture whereby the location pattern of principal roads can be relatively easily known) and a photo picture (a picture whereby the peripheral situation can be relatively easily known) are displayed on the same display screen, so that, for example, the location pattern of roads in an urban district and the peripheral situation can be effectively known.

[0058] An image display (15) according to the present invention is characterized by comprising a seventh photo picture preparing device to prepare a photo picture based on photo data read from a first photo data storage device in which photo data showing the surface of the earth is stored, and a seventh photo picture display device to display a photo picture which is prepared by the seventh photo picture preparing device, wherein the seventh photo picture preparing device prepares a photo picture on which prescribed image processing is conducted based on a predetermined condition.

[0059] Using the above image display (15), since a photo picture prepared with conducting prescribed processing (such as filtering) thereon on the basis of a predetermined condition (such as time periods) is displayed, for example, a night photo picture can be displayed after sunset, resulting in realization of a unit which gives high satisfaction to the user.

[0060] An image display (16) according to the present invention is characterized by being an image display which has a display control device to display a map image and a real image on the same scale concerning the same area on a display screen based on map data and real image data, wherein the display control device has a function of composing the map image and the real image so that in the background of either of the map image and the real image, the other image is overlaid in a given region, and only the other image can be seen in the composite region.

[0061] Using the above image display (16), either image of the map image and the real image (such as a satellite photograph or an air photograph) is made a background and the other image is overlaid thereon on the same scale (reduced scale) for display in the given region. And the composition of these images is further conducted so that only the other image can be seen in the region where these images are combined.

[0062] For example, when the map image is made a background, a coefficient of composition of the map image is set to be 0 in the given region, while that of the real image is set to be 1, so as to conduct the composition of these images. In the given region, only the real image can be seen. As a result, on the display screen, with the map image as a background, only the real image is fitted in part thereof for display, so that landmarks and the like can be grasped variously.

[0063] An image display (17) according to the present invention is characterized by being an image display which has a display control device to display a map image and a real image on the same scale concerning the same area on a display screen based on map data and real image data, wherein the display control device has a function of composing the map image and the real image so that in the background of either of the map image and the real image, the other image is overlaid in a given region, and through either of the map image and the real image, the other image can be seen in the whole or part of the composite region.

[0064] Using the above image display (17), with either the map image or the real image (such as a satellite photograph or an air photograph) as a background, the other image is overlaid thereon on the same scale (reduced scale) in the given region. For example, when the map image is made a background, on the display screen, with the map image as a background, the real image is overlaid on part thereof for display, so that landmarks and the like can be grasped variously.

[0065] Moreover, using the above image display (17), in the whole region or part of the region where these images are combined, these images are composed so that through either of these images, the other image can be seen.

[0066] For example, when the map image is made a background, a coefficient of composition of the map image is set to be α (0≦α<1) in the given region, while that of the real image is set to be β (=1−α) therein, so as to conduct the composition of these images. In the given region, the map image can be seen through (the whole or part of) the real image. As a result, it becomes possible to provide a considerably large amount of information to a user.

[0067] An image display (18) according to the present invention is characterized by comprising a composition level setting device which enables the setting of the composition level of the images, wherein the display control device composes the images based on the composition level set by the composition level setting device concerning the composite region in the above image display (17).

[0068] Using the above image display (18), since the setting of the composition level can be conducted, the user can freely make adjustments such as making the display brightness of the map image higher (that of the real image lower), or conversely making the display brightness of the real image higher (that of the map image lower) concerning the region where these images are combined. As a result, a display condition according to the user's preference can be realized.

[0069] An image display (19) according to the present invention is characterized by the display control device, composing the images so that the display brightness of a background image becomes higher from the composite region toward the outside of the region in the above image display (17) or (18).

[0070] Using the above image display (19), since the composition of these images is conducted so that the display brightness of an image which is a background is made higher from the composite region toward the outside of the region, the smooth shift of the images from the composite region to the outside thereof can be achieved.

[0071] An image display (20) according to the present invention is characterized by the image display, being adopted in a navigation system which can guide oneself to a goal by providing information such as routes and maps required for reaching the goal to a user, wherein the given region is any of a peripheral area of the one's own obtained based on the one's position information, a peripheral area of the goal obtained based on the goal position information, a peripheral area of a preset facility obtained based on the preset facility position information, and a peripheral area of a preselected position obtained based on position information of the preselected position previously pointed by the user in any of the above image displays (16)-(19).

[0072] Using the above image display (20), the given region is any of the peripheral area of the one's own, that of the goal, that of the preset facility (such as a station), and that of the preselected position (such as the user's home position) previously pointed by the user. Therefore, for example, when the map image is a background, these areas are shown using the real images.

[0073] As a result, since an area to be noted is displayed using an image having a quality different from a background image, it is possible to differentiate the noted area from the other portion.

[0074] An image display (21) according to the present invention is characterized by the image display, being adopted in a navigation system which can guide oneself to a goal by providing information such as routes and maps required for reaching the goal to a user, wherein the given region is an almost upper half region or an almost lower half region on the display screen in any of the above image displays (16)-(19).

[0075] Using the above image display (21), since the given region is an almost upper half region or an almost lower half region on the display screen, the almost upper half region can be displayed with the map image while the remaining almost lower half region can be displayed with the real image, or vice versa.

[0076] In a navigation system, in many cases, the periphery of the one's current position is displayed in the lower portion of the display screen, while the place remote from the one's current position is displayed in the upper portion of the display screen. Therefore, using the image display (21), on the basis of the one's current position, an image on this side and that on the remote side can be differentiated (see FIG. 18).

[0077] An image display (22) according to the present invention is characterized by the image display, being adopted in a navigation system which can guide oneself to a goal by providing information such as routes and maps required for reaching the goal to a user, wherein the given region is a peripheral area of the route obtained based on route information regarding the route in any of the above image displays (16)-(19).

[0078] Using the above image display (22), the given region is a peripheral area of the route. Therefore, for example, when the map image is a background, the route peripheral area is displayed using the real image.

[0079] As a result, since the route peripheral area is displayed using an image having a quality different from a background image, it is possible to differentiate the route peripheral area from the other portion.

[0080] An image display (23) according to the present invention is characterized by being an image display which has a first display control device to display a map image based on map data on a display screen, comprising a second display control device to display real images showing prescribed places on the same scale as the map image in the spaces of the prescribed places on the map image, based on space information showing the spaces of the prescribed places on the map and real image data formed so as to be able to correspond to the position coordinates.

[0081] Using the above image display (23), in the spaces of the prescribed places (places where a service station, a school, a park and the like exist) on the map image appearing on the display screen, the real images (e.g. satellite photographs or air photographs) showing the prescribed places on the same scale as the map image are displayed (see FIG. 23).

[0082] In a conventional image display, for example, in order to make it easy to grasp the situation in a map image appearing on a display screen, prominent marks such as a service station and a school, so-called landmarks are displayed on the map image. In the above image display (23), however, real images showing facilities such as a service station and a school on the same scale as the map image are displayed. Therefore, the places appearing on the map image are real images, as a matter of course, and the sizes (plot areas) thereof are also displayed similarly to the actual ones, so that it can be made considerably easy to grasp the situation shown by the map image.

[0083] An image display (24) according to the present invention is characterized by being an image display which has a first display control device to display a map image based on map data on a display screen, comprising a block computing device to find a block where a prescribed place is included based on address information showing the address of the prescribed place, and a third display control device to display a real image showing a block on the same scale as the map image in the space of the block on the map image, based on space information showing the space of the block computed by the block computing device and real image data formed so as to be able to correspond to the position coordinates.

[0084] Using the above image display (24), in the space of a block (a range in which a park or the like is enclosed by relatively wide roads such as principal roads) including the prescribed place (a place where a service station, a school, a park or the like exists) on the map image appearing on the display screen, the real image (e.g. a satellite photograph or an air photograph) showing the block on the same scale as the map image is displayed (see FIG. 25).

[0085] Therefore, the place appearing on the map image is a real image, as a matter of course, and the size (plot area) thereof is also displayed similarly to the actual one, so that it can be made considerably easy to grasp the situation shown by the map image. In addition, since not only the place but also the block where the place is included is displayed using a real image, it is possible to inform the user of the actual situation of not only the place but also the periphery thereof.

[0086] When a real image which looks as if only the prescribed place were cut out is displayed on the map image as shown in the below-described FIG. 23, space information (or two-dimensional information) showing the space (or a plane) of a facility such as a school as information regarding the facility is required. However, when a real image showing a block where the prescribed place is included is displayed, address information showing the address (or a point) of a facility such as a school is enough. Therefore, the above image display (24) has an advantage that to prepare not the space information of a high level but the address information of a relatively low level is only required.

[0087] An image display (25) according to the present invention is characterized by being an image display which has a first display control device to display a map image based on map data on a display screen, comprising a second display control device to display a real image showing a prescribed place on the same scale as the map image in the space of the prescribed place on the map image, based on space information showing the space of the prescribed place on the map and real image data formed so as to be able to correspond to the position coordinates, a block computing device to find a block where the prescribed place is included based on address information showing the address of the prescribed place, a third display control device to display a real image showing a block on the same scale as the map image in the space of the block on the map image, based on space information showing the space of the block computed by the block computing device and the real image data, and a switching control device to control the proper use of the control by the second display control device and the control by the third display control device, depending on a predetermined condition.

[0088] Using the above image display (25), a function of displaying the real image showing the prescribed place on the same scale as the map image in the space of the prescribed place on the map image appearing on the display screen, and a function of displaying the real image showing the block on the same scale as the map image in the space of the block where the prescribed place is included on the map image are available. Furthermore, these functions are properly used, depending on the predetermined condition. Therefore, since how to display a real image is properly changed depending on the condition, a more useful display mode can be realized (see FIG. 27).

[0089] Here, as the predetermined condition, usages of the prescribed places (such as classes of facilities) are exemplified. And as for a place such as a park whose boundary is ambiguous and hard to know, a real image showing not only the park itself but also a wide range (block) including the park is displayed on the map image.

[0090] An image display (26) according to the present invention is characterized by comprising a place selection device which enables a selection of a specific place, wherein the prescribed place is the specific place selected by the place selection device in any of the above image displays (23)-(25).

[0091] Using the above image display (26), which has the place selection device, the user can freely select the specific place, and moreover, a real image showing the place selected by the user can be displayed on the map image. Therefore, a display mode which serves the user's desire can be realized.

[0092] An image display (27) according to the present invention is characterized by comprising a usage selection device which enables a selection of a usage of a place, wherein the prescribed place is a place used for the usage selected by the usage selection device in any of the above image displays (23)-(25).

[0093] Using the above image display (27), which has the usage selection device, the user can freely select a usage of a place (such as a class of a facility), and moreover, a real image showing a place used for the usage selected by the user can be displayed on the map image. Therefore, a display mode which serves the user's desire can be realized.

[0094] An image display (28) according to the present invention is characterized by an image display, being adopted in a navigation system which can guide oneself to a goal by providing information such as routes and maps required for reaching the goal to a user, comprising a storage device to store information regarding the past driving record of the one's own and a place computing device to find a specific place based on the driving record stored in the storage device, wherein the prescribed place is a place computed by the place computing device.

[0095] Using the above image display (28), a real image showing a specific place (e.g. a place where a facility to which a visit was paid in the past exists) obtained based on the one's past driving record can be displayed on the map image. Therefore, since a place related to the past record of the user can be displayed as a real image, the past record can be ascertained through the contents displayed on the display screen.

[0096] An image display (29) according to the present invention is characterized by an image display which has a first display control device to display a map image based on map data on a display screen, comprising a fourth display control device to display a real image showing a prescribed block on the same scale as the map image in the space of the block on the map image, based on space information showing the space of the prescribed block and real image data formed so as to be able to correspond to the position coordinates.

[0097] Using the above image display (29), in the space of the prescribed block (e.g. a range where a park or the like is enclosed by relatively wide roads such as principal roads) on the map image appearing on the display screen, the real image showing the prescribed block on the same scale as the map image is displayed (see FIG. 31).

[0098] That is, the real image is displayed as if it were inlaid in the space of the prescribed block, so that it can be made considerably easy to grasp the situation shown by the map image.

[0099] An image display (30) according to the present invention is characterized by an image display, being adopted in a navigation system which can guide oneself to a goal by providing information such as routes and maps required for reaching the goal to a user, comprising a storage device to store information regarding the past driving record of the one's own, and a zone computing device to find a specific zone based on the driving record stored in the storage device, wherein the prescribed block is a block including a zone computed by the zone computing device in the above image display (29).

[0100] Using the above image display (30), a real image showing a specific block obtained based on the one's past driving record (e.g. a block including a place where a facility to which a visit was paid in the past exists) can be displayed on the map image. Therefore, since a block related to the past record of the user can be displayed as a real image, the past record can be ascertained through the contents displayed on the display screen.

[0101] An image display (31) according to the present invention is characterized by being an image display which has a fifth display control device to display a real image such as a satellite photograph or an air photograph showing the surface of the earth on a display screen, based on real image data formed so as to be able to correspond to the position coordinates, wherein the fifth display control device differentiates a prescribed block from the other portion to display the real image, based on space information showing the space of the prescribed block and the real image data.

[0102] Using the above image display (31), when the real image is displayed on the display screen, the prescribed block (e.g. the block to which the user has ever been) is differentiated from the other portion (e.g. blocks to which the user has never been) to display the real image (see FIG. 33).

[0103] Therefore, since the user can know a block to be more noticeable in an instant, a considerably useful unit can be realized. Here, as a method for differentiating the displays, a method wherein one is a color display while the other is a monochrome display is exemplified.

[0104] An image display (32) according to the present invention is characterized by comprising a block selection device which enables a selection of a specific block, wherein the prescribed block is the specific block selected by the block selection device in the above image display (31).

[0105] Using the above image display (32), which has the block selection device, the user can freely select the specific block, and moreover, it is possible to differentiate the display of the block selected by the user from the other portion. Therefore, a display mode which serves the user's desire can be realized.

[0106] An image display (33) according to the present invention is characterized by being an image display, being adopted in a navigation system which can guide oneself to a goal by providing information such as routes and maps required for reaching the goal to a user, comprising a storage device to store information regarding the past driving record of the one's own, and a zone computing device to find a specific zone based on the driving record stored in the storage device, wherein the prescribed block is a block including a zone computed by the zone computing device in the above image display (31).

[0107] Using the above image display (33), it is possible to differentiate in display a specific block (e.g. a block including a place where a facility to which a visit was paid in the past exists) obtained based on the one's past driving record from the other portion. Therefore, through the contents displayed on the display screen, the user can know to which area he/she has ever been and the like in an instant.

[0108] An image display (34) according to the present invention is characterized by being an image display which has a fifth display control device to display a real image such as a satellite photograph or an air photograph showing the surface of the earth on a display screen, based on real image data formed so as to be able to correspond to the position coordinates, wherein the fifth display control device displays a real image such as a satellite photograph or an air photograph showing a specific area based on information showing the specific area such as a park or a facility.

[0109] Using the above image display (34), a real image showing a specific area is displayed on the display screen, based on information showing the specific area (e.g. a park or a facility). Therefore, a cut-out satellite photograph or the like showing only a park, a facility or the like can be displayed on the display screen. Here, as a method for swiftly conducting display processing of the real image, a method wherein information regarding plots (areas) of parks or facilities is previously prepared is exemplified.

[0110] An image display (35) according to the present invention is characterized by being an image display which has a sixth display control device to display a real image such as a satellite photograph or an air photograph showing the periphery of a specific position on a display screen, based on real image data formed so as to be able to correspond to the position coordinates and position information of the specific position such as one's position, comprising a specific position display device to show the specific position on a real image appearing on the display screen.

[0111] Using the above image display (35), a real image showing the periphery of a specific position (such as one's car position) is displayed on the display screen, and moreover, the specific position is shown on the real image. Therefore, even in the case of a real image such as a satellite photograph appearing, the user can know around where his/her car is running.

BRIEF DESCRIPTION OF THE DRAWINGS

[0112]FIG. 1 is a block diagram schematically showing the principal part of a navigation system in which an image display according to an embodiment (1) of the present invention is adopted;

[0113]FIG. 2 is a flow chart showing the processing operation performed by a microcomputer in the navigation system in which the image display according to the embodiment (1) is adopted;

[0114]FIG. 3 is a flow chart showing the processing operation performed by the microcomputer in the navigation system in which the image display according to the embodiment (1) is adopted;

[0115] FIGS. 4(a) and 4(b) are illustrations showing a state where a map picture is displayed on a display panel;

[0116]FIG. 5 is an illustration showing a state where a photo picture is displayed on the display panel;

[0117]FIG. 6 is an illustration showing a state where a one's car position mark appearing on the photo picture was updated;

[0118]FIG. 7 is a flow chart showing the processing operation performed by a microcomputer in a navigation system in which an image display according to an embodiment (2) is adopted;

[0119]FIG. 8 is an illustration showing a state where button switches for selecting spots appear on a map;

[0120]FIG. 9 is a flow chart showing the processing operation performed by a microcomputer in a navigation system in which an image display according to an embodiment (3) is adopted;

[0121]FIG. 10 is a flow chart showing the processing operation performed by a microcomputer in a navigation system in which an image display according to an embodiment (4) is adopted;

[0122] FIGS. 11(a)-11(h) are illustrations showing a state where a photo picture display is shifting to a map picture display;

[0123]FIG. 12 is a block diagram schematically showing the principal part of a navigation system in which an image display according to an embodiment (5) of the present invention is adopted;

[0124]FIG. 13 is a flow chart showing the processing operation performed by a microcomputer in the navigation system in which the image display according to the embodiment (5) is adopted;

[0125]FIG. 14 is an illustration showing an example of a screen state displayed on a display panel of the navigation system in which the image display according to the embodiment (5) is adopted;

[0126]FIG. 15 is a flow chart showing the processing operation performed by a microcomputer in a navigation system in which an image display according to an embodiment (6) is adopted;

[0127]FIG. 16 is an illustration showing an operation screen displayed on a display panel of a navigation system in which an image display according to another embodiment is adopted;

[0128]FIG. 17 is a flow chart showing the processing operation performed by a microcomputer in a navigation system in which an image display according to an embodiment (7) is adopted;

[0129]FIG. 18 is an illustration showing an example of a screen state displayed on a display panel of a navigation system in which an image display according to another embodiment is adopted;

[0130]FIG. 19 is an illustration for descriptions of the relationship among nodes, links and interpolated points;

[0131]FIG. 20 is an illustration showing an example of the construction of facility data stored in a DVD-ROM in a navigation system in which an image display according to an embodiment (8) is adopted;

[0132]FIG. 21 is an illustration for descriptions of address coordinates and space information;

[0133]FIG. 22 is a flow chart showing the processing operation performed by a microcomputer in the navigation system in which the image display according to the embodiment (8) is adopted;

[0134]FIG. 23 is an illustration showing an example of a screen state displayed on a display panel of the navigation system in which the image display according to the embodiment (8) is adopted;

[0135]FIG. 24 is a flow chart showing the processing operation performed by a microcomputer in a navigation system in which an image display according to an embodiment (9) is adopted;

[0136]FIG. 25 is an illustration showing an example of a screen state displayed on a display panel of the navigation system in which the image display according to the embodiment (9) is adopted;

[0137] FIGS. 26(a) and 26(b) are flow charts showing the processing operation performed by a microcomputer in a navigation system in which an image display according to an embodiment (10) is adopted;

[0138]FIG. 27 is an illustration showing an example of a screen state displayed on a display panel of the navigation system in which the image display according to the embodiment (10) is adopted;

[0139]FIG. 28 is an illustration showing an example of an operation screen displayed on a display panel of a navigation system in which an image display according to another embodiment is adopted;

[0140]FIG. 29 is a flow chart showing the processing operation performed by a microcomputer in a navigation system in which an image display according to an embodiment (11) is adopted;

[0141]FIG. 30 is an illustration for descriptions of a state where a map picture is partitioned into a certain number of regions;

[0142]FIG. 31 is an illustration showing an example of a screen state displayed on a display panel of the navigation system in which the image display according to the embodiment (11) is adopted;

[0143]FIG. 32 is a flow chart showing the processing operation performed by a microcomputer in a navigation system in which an image display according to an embodiment (12) is adopted;

[0144]FIG. 33 is an illustration showing an example of a screen state displayed on a display panel of the navigation system in which the image display according to the embodiment (12) is adopted; and

[0145]FIG. 34 is a block diagram schematically showing the principal part of a navigation system in which a conventional image display is adopted.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0146] The preferred embodiments of the image display according to the present invention are described below by reference to those figures. FIG. 1 is a block diagram schematically showing the principal part of a navigation system in which an image display according to an embodiment (1) is adopted. Here, the same components as those of the navigation system shown in FIG. 34 are similarly marked, which are not described below.

[0147] A speed sensor 2 and a gyro sensor 3 are connected to a microcomputer 11, which concludes the position of one's car based on the computed distance traveled and the direction headed (self-contained navigation). In addition, a GPS receiver 4 is connected to the microcomputer 11, which concludes the position of one's car based on GPS signals (GPS navigation).

[0148] A DVD drive 6, which can capture electronic map data, photo data and the like from a DVD-ROM 17 (a storage device such as a CD-ROM is also allowed) in which electronic map data covering all over the country, and photo data such as satellite photographs or air photographs showing the surface of the earth covering limited recorded areas (e.g. the major cities) are recorded, is connected to the microcomputer 11, which based on the concluded current position of the one's car, calls up required map data or photo data from the DVD-ROM 17 and allows the same to be temporarily stored in a buffer memory 18 within the microcomputer 11. In the DVD-ROM 17, as photo data showing the surface of the earth covering the same area, for example, photographs on the scale of 1 m per pixel and those on the scale of 4 m per pixel are recorded.

[0149] At the top, bottom and both sides of a display panel 9 b, multiple infrared LEDs and multiple phototransistors are arranged in the opposed positions to each other so that the locations where a finger touched the display panel 9 b can be detected. The detected results can be acquired by the microcomputer 11.

[0150] The processing operation {circle over (1)} performed by the microcomputer 11 in the navigation system in which the image display according to the embodiment (1) is adopted is described below by reference to flow charts shown in FIGS. 2 and 3. First, the current position of one's car is computed from GPS signals and the like (Step 1), and based on the computed one's car current position information and map data stored in the buffer memory 18, a map picture showing the periphery of the one's car current position is prepared (Step 2). Here, the data regarding the prepared map picture is stored in the buffer memory 18 and read out in accordance with the display timing.

[0151] Based on the one's car current position information and photo data stored in the buffer memory 18, whether the one's car is within the recorded areas (e.g. the major cities such as Tokyo and Osaka) or not is judged (Step 3). When the one's car is judged to be within the recorded areas, photo pictures of two types (e.g. a photo picture of a wide-area display and a photo picture of a detailed display) showing the periphery of the one's car current position are prepared, based on the one's car current position information and the photo data on the two types of scales stored in the buffer memory 18 (Step 4). Here, the data regarding the prepared photo pictures is stored in the buffer memory 18 and read out in accordance with the display timing.

[0152] Then, whether or not a flag f₁ showing that the screen displayed on the display panel 9 b was switched from a map picture to a photo picture is 1 is judged (Step 5). When it is judged that the flag f₁ is not 1, or that the screen is not switched to a photo picture, whether or not a flag f₂ showing that display switching to a photo picture is possible (or the one's car is within the recorded areas) is 1 is judged (Step 6). When the flag f₂ is judged not to be 1, a “PHOTO PICTURE” button switch (touch switch) for a user's command to conduct the display switching from a map picture to a photo picture is formed (Step 7). Then, the flag f₂ is changed to 1 (Step 8), and the operation goes to Step 9. FIGS. 4(a) and 4(b) are illustrations showing a state where a map picture is displayed on the display panel 9 b, and in FIG. 4(b), the “PHOTO PICTURE” button switch is displayed on the map picture.

[0153] On the other hand, when it is judged that the flag f₂ is 1, or that the “PHOTO PICTURE” button switch has been already formed in Step 6, it bypasses Steps 7 and 8, and goes direct to Step 9.

[0154] In Step 9, whether or not the “PHOTO PICTURE” button switch was touched by the user is judged. When the “PHOTO PICTURE” button switch is judged to have been touched, the “PHOTO PICTURE” button switch is cleared (Step 10), and the flag f₂ is changed to 0 (Step 11). Then, as a photo picture (such as a photo picture of a wide-area display) showing the periphery of the one's car current position is displayed, a one's car position mark showing the one's car current position is displayed on the photo picture (Step 12). Here, as a method for displaying the one's car position mark on the photo picture, a method wherein the latitudes and longitudes of the upper left and lower right points of the rectangular area shown by the photo data are used is exemplified.

[0155] After the processing in Step 12, a “RETURN” button switch for the user's command to change back the display from the photo picture to the map picture and a “SCALE CHANGE” button switch for the user's command to change the reduced scale of the photo picture are additionally formed (Steps 13 and 14), and then, the flag f₁ is changed to 1 (Step 15). In FIG. 5, a state where a photo picture is displayed on the display panel 9 b is shown.

[0156] On the other hand, when the “PHOTO PICTURE” button switch is judged not to have been touched in Step 9, the map picture is updated based on the one's car current position information (Step 16).

[0157] By the way, when it is judged that the flag f₁ is 1, or that the display has been switched to a photo picture in Step 5, whether the “RETURN” button switch was touched or not is judged (Step 17). When the “RETURN” button switch is judged to have been touched, the “RETURN” button switch and the “SCALE CHANGE” button switch are cleared from the screen (Steps 18 and 19), and then, the flag f₁ is changed to 0 (Step 20).

[0158] After that, a map picture showing the periphery of the one's car current position is displayed (Step 21), the “PHOTO PICTURE” button switch is formed (Step 22), and then, the flag f₂ is changed to 1 (Step 23).

[0159] On the other hand, when the “RETURN” button switch is judged not to have been touched in Step 17, whether the “SCALE CHANGE” button switch was touched or not is judged (Step 24). When the “SCALE CHANGE” button switch is judged to have been touched, the reduced scale of the photo picture is changed (Step 25), and based on the one's car current position information, the one's car position mark appearing on the photo picture is updated (Step 26). In FIG. 6, a state where the one's car position mark appearing on a photo picture was updated is shown.

[0160] Here, the changing of the reduced scales of photo pictures is conducted, for example, by reading data regarding a photo picture of a detailed display from the buffer memory 18 to display a photo picture of a detailed display in the case of a photo picture of a wide-area display appearing, while by reading data regarding a photo picture of a wide-area display from the buffer memory 18 to display a photo picture of a wide-area display in the case of a photo picture of a detailed display appearing.

[0161] When the “SCALE CHANGE” button switch is judged not to have been touched in Step 24, it is not necessary to change the reduced scale of the photo picture, so that it bypasses Step 25 and goes to Step 26, wherein based on the one's car current position information, the one's car position mark appearing on the photo picture is updated.

[0162] By the way, when the one's car is judged not to be within the recorded areas in Step 3, whether or not the flag f₁ showing that the display was switched from the map picture to the photo picture is 1 is judged (Step 31). When it is judged that the flag f₁ is not 1, or that the map picture is displayed, whether or not the flag f₂ showing that the display changing to a photo picture is possible (or the one's car is within the recorded areas) is 1 is judged (Step 32).

[0163] When it is judged that the flag f₂ is 1, or the “PHOTO PICTURE” button switch has been formed, the “PHOTO PICTURE” button switch is cleared (Step 33), and then, the flag f₂ is changed to 0 (Step 34).

[0164] On the other hand, when the flag f₂ is judged not to be 1 in Step 32, it is not necessary to conduct the processing operation in Steps 33 and 34, so that the processing operation {circle over (1)} is ended at once.

[0165] When it is judged that the flag f₁ is 1, or that a photo picture is displayed in Step 31, whether the “RETURN” button switch was touched by the user or not is judged (Step 35). When the “RETURN” button switch is judged to have been touched, the “RETURN” button switch and the “SCALE CHANGE” button switch are cleared (Steps 36 and 37), and the flag f₁ is changed to 0 (Step 38). Then, a map picture showing the periphery of the one's car current position is displayed (Step 39).

[0166] On the other hand, when the “RETURN” button switch is judged not to have been touched in Step 35, it is not necessary to return the display to a map picture, so that the processing operation {circle over (1)} is ended at once.

[0167] Using the navigation system in which the image display according to the embodiment (1) is adopted, when one's car goes into an area whose photo data is recorded (e.g. a major city such as Tokyo or Osaka), a “PHOTO PICTURE” button switch is displayed, so that the user can easily know that he/she has been in an area where photo pictures can be displayed.

[0168] When the “PHOTO PICTURE” button switch is touched by the user, the display is switched from a map picture to a photo picture showing the periphery of the one's car current position. Therefore, by seeing the photo picture, the user can easily know the one's car current position, and easily grasp the actual situation around the current position.

[0169] In the navigation system in which the image display according to the embodiment (1) is adopted, the user is taught that he/she entered an area where photo pictures can be displayed by displaying the “PHOTO PICTURE” button switch, and by the user's touch of the “PHOTO PICTURE” button switch, the display switching is conducted. However, in an image display according to another embodiment, the user may be taught that he/she entered an area where photo pictures can be displayed by changing the shape or color of a one's car position mark, and by the user's touch of the one's car position mark whose shape or color changed, the display switching may be conducted.

[0170] Here, only the case where a map picture is completely switched to a photo picture is described, but when the photo picture is displayed, the display space of the map picture may be made smaller and the photo picture may be displayed in the unoccupied space, or the photo picture may be overlaid on the map picture for display.

[0171] In the navigation system in which the image display according to the embodiment (1) is adopted, a photo picture is displayed according to the user's command for switching, but in a navigation system according to another embodiment, when one's car enters the recorded area, a photo picture showing the periphery of the one's car current position may be automatically displayed. Here, in this case, a method wherein a map picture is completely switched to a photo picture may be allowed, but a method wherein the display space for a map picture is made smaller and a photo picture is displayed in the space available is more desirable.

[0172] In the navigation system in which the image display according to the embodiment (1) is adopted, in consideration of photo data, having an considerably large amount of data, so that it takes considerably much time to read photo data from a storage device or process images, the DVD-ROM 17 in which photo data of two types on different scales to one area is recorded is adopted. However, if it becomes possible to conduct the image processing and the like on photo data at high speeds, not a recording medium in which photo data of two or more types is recorded but a recording medium in which photo data of one type on a smaller scale (e.g. a scale of 1 m per pixel, or detailed image data) is recorded may be adopted.

[0173] A navigation system in which an image display according to an embodiment (2) is adopted is described below. Here, since the construction of the navigation system in which the image display according to the embodiment (2) is adopted is similar to that of the navigation system shown in FIG. 1 except for the microcomputer 11, a microcomputer is marked differently and others are not described below.

[0174] The processing operation {circle over (2)} performed by the microcomputer 11A in the navigation system in which the image display according to the embodiment (2) is adopted is described below by reference to a flow chart shown in FIG. 7. First, in Steps 41-43, whether the below-described flags f₃-f₅ are 1 or not is judged. When the flags f₃-f₅ each are judged not to be 1, the operation goes to Step 44, wherein whether or not the selection of a route was completed with entries of a goal and the like by the user is judged.

[0175] When the selection of a route is judged not to have been completed, the processing operation {circle over (2)} is ended at once. On the other hand, when the selection of a route is judged to have been completed, whether or not the selected route runs within a recorded area (such as a major city) of photo data recorded in a DVD-ROM 17 is judged (Step 45). When it is judged to run within the recorded area, whether or not prescribed spots (such as interchanges and tourist spots) exist on or around the selected route is judged (Step 46).

[0176] When the prescribed spots are judged to exist on or around the route, photo data required (or photo data regarding the prescribed spots existing on or around the route) is read from the DVD-ROM 17, and based on the read photo data, photo pictures showing the prescribed spots are prepared (Step 47). Here, the data regarding the photo pictures showing the prescribed spots is stored in a buffer memory 18.

[0177] Then, the route is displayed on the screen (Step 48), button switches for the user's commands to display photo pictures showing the prescribed spots are formed so as to correspond to the locations of the spots (Step 49), and the flag f₄ showing that the button switches are formed is changed to 1 (Step 50). In FIG. 8, a state where the button switches are displayed on a map is shown.

[0178] Here, as for the button switches, how to represent each kind of spots is previously determined as shown in FIG. 8. For example, an interchange is determined to be represented by an “IC” and a service area is determined to be represented by a “SA”, so that the user can easily select a spot he/she desires.

[0179] Whether or not a termination command of the route display was given through operating a remote control 8 or the like is judged (Step 51). When the termination command of the route display is judged not to have been given by the user, whether or not a button switch such as an “IC” appearing on the screen was touched is judged (Step 52).

[0180] When the button switches are judged not to have been touched, the processing operation {circle over (2)} is ended at once. On the other hand, when a button switch is judged to have been touched, a photo picture showing a spot corresponding to the touched button switch is displayed (Step 53), a “RETURN” button switch for the user's command to return the display to the picture in which the route is shown is formed (Step 54), the flag f₄ is changed to 0 (Step 55), and then, the flag f₅ showing that a photo picture showing a spot is displayed is changed to 1 (Step 56).

[0181] Whether or not the “RETURN” button switch was touched by the user is judged (Step 57). When it is judged to have been touched, the operation returns to Step 48, wherein the route is displayed. On the other hand, when it is judged not to have been touched, the processing operation {circle over (2)} is ended at once.

[0182] When the termination command of the route display is judged to have been given by the user in Step 51, a menu screen is displayed (Step 58), and the flag f₄ is changed to 0 (Step 59).

[0183] When the selected route is judged not to run within the recorded areas in Step 45, or when the prescribed spots are judged not to exist on or around the selected route in Step 46, the operation goes to Step 60, wherein the route is displayed, and the flag f₃ showing that the route display is conducted in the same manner as before is changed to 1 (Step 61).

[0184] Whether or not a command to terminate the route display was given through operating the remote control 8 or the like is judged (Step 62). When the command to terminate the route display is judged to have been given by the user, the menu screen is displayed (Step 63), and the flag f₃ is changed to 0 (Step 64). On the other hand, when the termination command is judged not to have been given, the processing operation {circle over (2)} is ended at once.

[0185] When it is judged that the flag f₃ is 1, or that the route is displayed in the same manner as before in Step 41, the operation goes to Step 62. When it is judged that the flag f₄ is 1, or that button switches for commands to display photo pictures showing spots have appeared in Step 42, it goes to Step 51, wherein whether a command to terminate the route display was given by the user or not is judged.

[0186] When it is judged that the flag f₅ is 1, or that a photo picture showing a spot has appeared in Step 43, it goes to Step 57, wherein whether the “RETURN” button switch was touched or not is judged.

[0187] Using the navigation system in which the image display according to the embodiment (2) is adopted, photo pictures showing prescribed spots (such as interchanges, service areas and tourist spots) existing on or around the selected route are displayed. As a result, places which are difficult to express on a map picture can be shown using photo pictures, so that the user can easily know the places. In addition, showing tourist spots and the like having a lot of good points worth seeing using photo pictures can make a drive and the like more enjoyable.

[0188] Since the button switches for commands to display the photo pictures are formed so as to correspond to each spot, the user can easily select a spot he/she desires.

[0189] A navigation system in which an image display according to an embodiment (3) is adopted is described below. Here, since the construction of the navigation system in which the image display according to the embodiment (3) is adopted is similar to that of the navigation system shown in FIG. 1 except for the microcomputer 11 and the DVD-ROM 17, a microcomputer and a DVD-ROM are marked differently and others are not described below.

[0190] In the DVD-ROM 17B, electronic map data covering all over the country, photo data such as satellite photographs or air photographs showing the surface of the earth, and detailed data (e.g. data regarding admission fees, business days and the like) regarding prescribed spots (e.g. places of amusement and restaurants) are recorded. Here, the recorded areas (such as the major cities) concerning the photo data are limited.

[0191] The processing operation {circle over (3)} performed by the microcomputer 11B in the navigation system in which the image display according to the embodiment (3) is adopted is described below by reference to a flow chart shown in FIG. 9. First, whether a flag f₆ showing that a photo picture is displayed is 1 or not is judged (Step 71). When it is judged that the flag f₆ is not 1, or that a photo picture is not displayed, whether or not it is the display timing of a photo picture (e.g. in a case where a command for display switching to a photo picture was given by a user) is judged (Step 72).

[0192] When it is judged not to be the display timing of a photo picture, the processing operation {circle over (3)} is ended at once, while when it is judged to be the display timing of a photo picture, whether or not prescribed spots (e.g. places of amusement and restaurants) whose detailed data is recorded exist within the area shown by a photo picture to be displayed is judged (Step 73).

[0193] When the prescribed spots are judged to exist therein, button switches for commands to provide detailed information regarding the prescribed spots are formed so as to correspond to each spot (Step 74), while the photo picture is displayed (Step 75), a “RETURN” button switch for the user's command to return the display from the photo picture to the preceding picture is formed (Step 76), and the flag f₆ is changed to 1 (Step 77).

[0194] On the other hand, when the prescribed spots are judged not to exist therein in Step 73, it bypasses Step 74, and goes to Step 75.

[0195] By the way, when it is judged that the flag f₆ is 1, or that a photo picture is displayed in Step 71, whether a flag f₇ showing that detailed information regarding a spot is displayed is 1 or not is judged (Step 78). When it is judged that the flag f₇ is not 1, or that the detailed information is not displayed, whether or not a button switch formed so as to correspond to each spot was touched is judged (Step 79).

[0196] When the button switch is judged to have been touched, detailed data regarding the corresponding spot is read out and based on the read detailed data, detailed information regarding the spot is displayed (Step 80), and the flag f₇ is changed to 1 (Step 81).

[0197] On the other hand, when the button switches are judged not to have been touched in Step 79, whether the “RETURN” button switch was touched or not is judged (Step 82). When the “RETURN” button switch is judged to have been touched by the user, the “RETURN” button switch is cleared (Step 83), the flag f₆ is changed to 0 (Step 84), and the picture preceding to the photo picture is displayed (Step 85). On the other hand, when the “RETURN” button switch is judged not to have been touched, the processing operation {circle over (3)} is ended at once.

[0198] When it is judged that the flag f₇ is 1, or that the detailed information has appeared in Step 78, whether the “RETURN” button switch was touched by the user or not is judged (Step 86). When the “RETURN” button switch is judged to have been touched, the flag f₇ is changed to 0 (Step 87), and the photo picture is displayed (Step 88). On the other hand, when the “RETURN” button switch is judged not to have been touched, the processing operation {circle over (3)} is ended at once.

[0199] Using the navigation system in which the image display according to the embodiment (3) is adopted, detailed information (e.g. information regarding admission fees, business days and the like) regarding spots (e.g. places of amusement and restaurants) which exist within the area shown by a displayed photo picture is provided to the user, so that an image display unit which gives higher satisfaction to the user can be realized.

[0200] In addition, since button switches for commands to provide the detailed information are formed so as to correspond to each spot, the user can easily select a spot he/she desires.

[0201] A navigation system in which an image display according to an embodiment (4) is adopted is described below. Here, since the construction of the navigation system in which the image display according to the embodiment (4) is adopted is similar to that of the navigation system shown in FIG. 1 except for the microcomputer 11, a microcomputer is marked differently and others are not described below.

[0202] The processing operation {circumflex over (4)} performed by the microcomputer 11C in the navigation system in which the image display according to the embodiment (4) is adopted is described below by reference to a flow chart shown in FIG. 10. First, the current position of one's car is computed from GPS signals and the like (Step 91), and whether or not a flag f₈ showing that photo data regarding the periphery of a goal was read form the DVD-ROM 17 is 1 is judged (Step 92).

[0203] When it is judged that the flag f₈ is not 1, or that the photo data has not been read out, whether the one's car can reach the goal within 10 minutes or not is judged based on the computed one's car current position information (Step 93). When the one's car is judged not to be able to reach the goal within 10 minutes, the processing operation {circle over (4)} is ended at once. On the other hand, when the one's car is judged to be able to reach the goal within 10 minutes, photo data regarding the periphery of the goal is read from the DVD-ROM 17 and stores the same in a buffer memory 18 (Step 94), the flag f₈ is changed to 1 (Step 95), and the operation goes to Step 96.

[0204] When it is judged that the flag f₈ is 1, or that the photo data has been already read out in Step 92, it bypasses Steps 93-95, and goes direct to Step 96.

[0205] In Step 96, based on the one's car current position information, whether the one's car can reach the goal within 3 minutes or not is judged. When the one's car is judged not to be able to reach the goal within 3 minutes, the processing operation {circle over (4)} is ended at once. On the other hand, when the one's car is judged to be able to reach the goal within 3 minutes, based on the photo data regarding the periphery of the goal stored in the buffer memory 18, a photo picture showing the periphery of the goal is prepared (Step 97), the prepared photo picture is displayed (Step 98), and the flag f₈ is changed to 0 (Step 99).

[0206] Using the navigation system in which the image display according to the embodiment (4) is adopted, since a photo picture showing the periphery of a goal is displayed, the user can obtain such various kinds of information regarding the goal such as information about whether the goal is in the midtown or not, information about whether the road is wide or narrow, information about whether the area is densely built-up or not and information about whether places of amusement or parking spaces exist.

[0207] In addition, since a photo picture showing the periphery of the goal is displayed when the one's car reaches close to the goal, the user can grasp the situation around the goal just before arriving at the goal.

[0208] Here, in the navigation system in which the image display according to the embodiment (4) is adopted, a photo picture showing the periphery of the goal is displayed when the one's car reaches close to the goal. However, in a navigation system according to another embodiment, the photo picture may be displayed when the goal was selected by the user, or the photo picture may be displayed when a display command was given by the user.

[0209] A map picture, a photo picture, a screen showing detailed information and the like to be displayed on the display panel 9 b in the navigation system in which the image display according to any of the embodiments (1)-(4) is adopted, may be displayed on the same screen, which enables the user to efficiently grasp information acquired from various kinds of pictures. When various kinds of pictures are displayed on the same screen, the differentiation of the display spaces and the like may be done according to the importance, the user's command or the like.

[0210] In the navigation system in which the image display according to any of the embodiments (1)-(4) is adopted, by conducting the display switching from a map picture to a photo picture and/or the display switching from the photo picture to the map picture with matching the area shown by the map picture with the area shown by the photo picture (matching the reduced scales, directions and locations of both the pictures), the display switching can be performed with giving no unnatural feeling to the user.

[0211] Furthermore, by conducting the display switching with the image processing of a fade-in and/or a fade-out (e.g. the transmittance of the screen display is variable in the 100% to 0% range), visually very excellent display switching can be achieved. Here, as a method for matching the reduced scales, directions and locations of both the pictures, matching the latitudes and longitudes of the upper left and lower right points of the rectangular area shown by map data with those of the rectangular area shown by photo data is exemplified.

[0212] By the way, photo data has a considerably large amount of data, compared with map data, so that it sometimes takes much time to read photo data from a storage device or process images. Therefore, it is difficult, for example, to update a picture according to one's travel with fixing the one's current position mark on the display, like in the case of using map data.

[0213] As one of methods for solving this problem, a method wherein with the photo picture fixed on the display panel 9 b, the one's current position mark is caused to move on the photo picture as shown in FIGS. 5 and 6 is exemplified. However, the photo picture is not updated according to the one's travel, so that the one's current position mark will go out of the photo picture (or the display panel 9 b) at last.

[0214] As a method for avoiding the occurrence of such situation, a method wherein in the case of display switching from the photo picture to the map picture, with matching the area shown by the map picture with the area shown by the photo picture, according to the travel of the one's car, the display area of the photo picture is made smaller while that of the map picture is made larger, and the display is gradually switched so that the one's car current position mark shifts onto the map picture before the one's car current mark goes out of the photo picture (the display panel 9 b), as shown in FIGS. 11(a)-11(h), is exemplified, which makes it possible to avoid the occurrence of the above situation, and also enables visually very excellent display switching.

[0215] In the navigation system in which the image display according to any of the embodiments (1)-(4) is adopted, by reading photo data based on a predetermined condition (such as photo data taken in winter) from a recording medium in which photo data taken in two or more situations (such as seasons or time periods) to one area and displaying a photo picture prepared based on the read photo data, for example, a photo picture (the situation of a snowy urban area) prepared based on photo data taken in winter in the case of December can be displayed, leading to realization of a navigation system having higher added values.

[0216] In the navigation system in which the image display according to any of the embodiments (1)-(4) is adopted, by displaying a photo picture on which a preset image processing (e.g. filtering) is conducted based on a predetermined condition (such as time periods), for example, a night photo picture can be displayed after sunset, leading to realization of a system which gives the user high satisfaction.

[0217]FIG. 12 is a block diagram schematically showing the principal part of a navigation system in which an image display according to an embodiment (5) is adopted.

[0218] A speed sensor 2 for acquiring information regarding the distance traveled by computation from the vehicle speed and a gyro sensor 3 for acquiring information regarding the direction headed are connected to a microcomputer 1, which concludes the position of one's car based on the computed traveled distance information and the headed direction information (self-contained navigation).

[0219] A GPS receiver 4, which receives GPS signals from satellites through an antenna 5, is connected to the microcomputer 1, which concludes the position of one's car based on the GPS signals (GPS navigation).

[0220] A DVD drive 6, which can capture map data or real image data from a DVD-ROM 17C (other storage devices are also allowed) in which the map data and the real image data of satellite photographs showing the surface of the earth are recorded, is connected to the microcomputer 1, which based on the concluded one's car current position information, route information regarding the below-described guidance route and the like, stores the map data or the real image data required from the DVD-ROM 17C into a RAM la within the microcomputer 1. Here, as a method for allowing the real image data to correspond to the position coordinates, a method wherein the latitudes and longitudes of the upper left and lower right points of the rectangular area shown by the real image data are used is exemplified.

[0221] By conducting the map-matching wherein the concluded one's car current position and the map data (the real image data) are matched, the microcomputer 1 can display a map image (real image) in which the current position of one's car is precisely shown on a display panel 9 b.

[0222] And switch signals output from a joystick 8 a or button switches 8 b arranged on a remote control 8, or switch signals output from button switches 9 a arranged on a monitor 9 are input to the microcomputer 1, in which the processing corresponding to these switch signals is conducted. For example, when capturing information of a goal or transit points from these switches, the microcomputer 1 finds an optimum route from the one's car current position (starting point) to the goal via the transit points and displays that as a guidance route with a map picture on the display panel 9 b.

[0223] At the top, bottom and both sides of the display panel 9 b, multiple infrared LEDs and multiple phototransistors are arranged in the opposed positions to each other, so that the locations where a finger touched the display panel 9 b can be detected. The detected results can be acquired by the microcomputer 1.

[0224] The processing operation {circle over (1)} performed by the microcomputer 1 in the navigation system in which the image display according to the embodiment (5) is adopted is described below by reference to a flow chart shown in FIG. 13. First, the current position of one's car is computed from the GPS signals and the like (Step 101), and based on the computed one's car current position information, an area E₁ around the one's car current position, for example, an area up to some hundreds of radius from the one's car current position in the center, is computed (Step 102), and based on the map data and the real image data stored in the RAM 1 a, regarding a region including the one's car current position, a map image is displayed as a background on the display panel 9 b and a real image on the same scale as the map image is displayed in the area E₁ (Step 103), and then, a mark M showing the one's car current position is displayed on the display panel 9 b (Step 104).

[0225] Here, the processing operation in Step 103 is described in more detail. In the case of displaying a map image corresponding to the map data in the remaining region except the area E₁ (an area E₀), the microcomputer 1 multiplies the map data by a coefficient of composition α₀ (=1), while in the case of displaying that in the area E₁, it multiplies the map data by a coefficient of composition α₁ (=0).

[0226] In the case of displaying a real image corresponding to the real image data in the area E₀, the microcomputer 1 multiplies the real image data by a coefficient of composition β₀ (=1−α₀, or 0), while in the case of displaying that in the area E₁, it multiplies the real image data by a coefficient of composition β₁ (=1−α₁, or 1).

[0227] That is, since the coefficient of composition α₀ is 1 (the coefficient of composition β₀ is 0), only the map image is displayed in the area E₀. And since the coefficient of composition α₁ is 0 (the coefficient of composition β₁ is 1), only the real image is displayed in the area E₁. In FIG. 14, a state where the map image is displayed in the area E₀ and the real image is displayed in the area E₁, is shown.

[0228] Using the navigation system in which the image display according to the embodiment (5) is adopted, with the map image as a background, only the real image (such as a satellite photograph or an air photograph) is fitted into the area E₁ of the periphery of the one's car current position for display on the same scale, so that landmarks and the like can be grasped variously.

[0229] A navigation system in which an image display according to an embodiment (6) is adopted is described below. Here, since the construction of the navigation system is similar to that of the navigation system shown in FIG. 12 except for the microcomputer 1, a microcomputer is marked differently and others are not described below.

[0230] The processing operation {circle over (2)} performed by the microcomputer 1A in the navigation system in which the image display according to the embodiment (6) is adopted is described below by reference to a flow chart shown in FIG. 15. First, the current position of one's car is computed from the GPS signals and the like (Step 111), and based on the computed one's car current position information, an area E₁ of the periphery of the one's car current position, for example, an area up to some hundreds of radius from the one's car current position in the center, is computed (Step 112), and based on the map data and the real image data stored in a RAM 1 a, regarding a region including the one's car current position, a map image is displayed as a background on the display panel 9 b and a real image on the same scale as the map image is displayed in an area E₁ (Step 113), and then, a mark M showing the one's car current position is displayed on the display panel 9 b (Step 114).

[0231] Here, the processing operation in Step 113 is described in more detail. In the case of displaying a map image corresponding to the map data in the remaining region except the area E₁ (an area E₀), the microcomputer 1A multiplies the map data by a coefficient of composition α₀ (=1), while in the case of displaying that in the area E₁, it multiplies the map data by a coefficient of composition α₁ (0≦α₁≦1), for example, 0.5.

[0232] In the case of displaying a real image corresponding to the real image data in the area E₀, the microcomputer 1A multiplies the real image data by a coefficient of composition β₀ (=1−α₀, or 0), while in the case of displaying that in the area E₁, it multiplies the real image data by a coefficient of composition β₁ (=1−α₁, for example, 0.5).

[0233] That is, since the coefficient of composition α₀ is 1 (the coefficient of composition β₀ is 0), only the map image is displayed in the area E₀. And since the coefficient of composition α₁ is 0.5 (the coefficient of composition β₁ is 0.5), the images are displayed so that the map image is seen through the real image in the area E₁.

[0234] Using the navigation system in which the image display according to the embodiment (6) is adopted, with the map image as a background, the real image (such as a satellite photograph or an air photograph) is overlaid thereon in the area E₁ of the periphery of the one's car current position for display on the same scale, so that landmarks and the like can be grasped variously.

[0235] Furthermore, since these images are synthesized so that the map image is seen through the real image, it is possible to provide the user with a considerably large amount of information.

[0236] Here, in the image display according to the above embodiment (6), in the case of displaying an image in the area E₁, the microcomputer 1A multiplies the map data by a coefficient of composition α₁ (=0.5), while it multiplies the real image data by a coefficient of composition β₁ (=1−α₁), and an image obtained by composing these images is displayed in the area E₁. However, in an image display according to another embodiment, a coefficient of composition α₁ may be varied within the area E₁.

[0237] For example, by setting a coefficient of composition α₁ to be 0 (setting a coefficient of composition β₁ to be 1) in the center portion of the area E₁, making the coefficient of composition α₁ larger toward the boundary between the area E₁ and the area E₀ so that the coefficient of composition α₁ becomes 1 just at the boundary, it is possible to make the image shift from the real image to the map image smooth.

[0238] In a navigation system in which an image display according to still another embodiment is adopted, through a screen displayed on the display panel 9 b, the user can carry out various types of setting. For example, through a “COMPOSITE LEVEL SETTING” screen as shown in FIG. 16, the user can freely set a coefficient of composition α₁, or a coefficient for determining the transmittance of the map picture to the real picture. Based on the contents set through the “COMPOSITE LEVEL SETTING” screen, the microcomputer 1A may conduct the composition of these images, which leads to realization of a display condition according to the user's preference.

[0239] For example, in the case where the “SATELLITE PHOTO PRIORITY” is selected by the user through the “COMPOSITE LEVEL SETTING” screen (see FIG. 16), the coefficient of composition α₁ is set to be 0.3 to synthesize images. In the case where “NORMAL” is selected, the coefficient of composition α₁ is set to be 0.5 to synthesize images. And in the case where “MAP PICTURE PRIORITY” is selected, the coefficient of composition α₁ is set to be 0.7 to synthesize images.

[0240] In the image display according to the above embodiment (5) or (6), a case where the real image is overlaid on the map image as a background in the peripheral area E₁ of the one's car current position is described, but the map image may be overlaid on the real image as a background in the peripheral area E₁ of the one's car current position. And it may be possible to allow the user to freely set the switching between these conditions.

[0241] In the image display according to the above embodiment (5) or (6), the map image is used as a background, and the real image is overlaid thereon in the peripheral area E₁ of the one's car current position. However, in an image display according to another embodiment, for example, the real image may be overlaid in the goal peripheral area, a peripheral area of a prescribed facility (such as a station) or a peripheral area of a preset position (such as the user's home position) pointed by the user in advance, and moreover, the real image may be displayed in the peripheral area of a guidance route based on route information regarding the guidance route for guiding to the goal. For example, the real image is displayed so as to lie along the guidance route with the map image as a background.

[0242] A navigation system in which an image display according to an embodiment (7) is adopted is described below. Here, since the construction of the navigation system is similar to that of the navigation system shown in FIG. 12 except for the microcomputer 1, a microcomputer is marked differently and others are not described below.

[0243] The processing operation {circle over (3)} performed by the microcomputer 1B in the navigation system in which the image display according to the embodiment (7) is adopted is described below by reference to a flow chart shown in FIG. 17. First, the current position of one's car is computed from the GPS signals and the like (Step 121), and based on the real image data and the map data stored in a RAM 1 a, regarding a region including the one's car current position, a real image is displayed in the upper area E_(U) on the display panel 9 b and a map image on the same scale as the real image is displayed in the lower area E_(D) thereon (Step 122), and then, a mark M showing the one's car current position is displayed on the display panel 9 b (Step 123).

[0244] Here, the processing operation in Step 122 is described in more detail. In the case of displaying a map image corresponding to the map data in the area E_(U), the microcomputer 1B multiplies the map data by a coefficient of composition α_(U) (=0), while in the case of displaying that in the area E_(D), it multiplies the map data by a coefficient of composition α_(D) (=1).

[0245] In the case of displaying a real image corresponding to the real image data in the area E_(U), the microcomputer 1B multiplies the real image data by a coefficient of composition β_(U) (=1−α_(U), or 1), while in the case of displaying that in the area E_(D), it multiplies the real image data by a coefficient of composition β_(D) (=1−α_(D), or 0). In FIG. 18, a state where the real image is displayed in the upper area E_(U) while the map image is displayed in the lower area E_(D) is shown.

[0246] Using the navigation system in which the image display according to the embodiment (7) is adopted, the real image is displayed in the upper area E_(U) on the display panel 9 b, while the map image is displayed in the lower area E_(D) on the display panel 9 b.

[0247] By the way, in a navigation system, in many cases, the periphery of the one's car current position is displayed in the lower portion on the display panel 9 b, while a place remote from the one's car current position is displayed in the upper portion on the display panel 9 b. Therefore, as described above, by displaying the real image in the area E_(U) while displaying the map image in the area E_(D) (the reverse case is also allowed, as a matter of course), it is possible to differentiate an image on this side from that on the remote side on the basis of the one's car current position.

[0248] Here, each image shown in FIGS. 14 and 18 is that of the earth's surface seen from almost directly above it (an angle of depression θ=90°) (a plane image), but in the present invention, it is not limited to such image seen from almost directly above the earth's surface. An image of the earth's surface seen slantingly (0°<an angle of depression θ<90°, e.g. θ=60°) may be displayed on the display panel 9 b.

[0249] A navigation system in which an image display according to an embodiment (8) is adopted is described below by reference to a block diagram shown in FIG. 12.

[0250] A speed sensor 2 for acquiring information regarding the distance traveled by computation from the vehicle speed and a gyro sensor 3 for acquiring information regarding the direction headed are connected to a microcomputer 1C, which can conclude the position of one's car based on the computed traveled distance information and the headed direction information (self-contained navigation).

[0251] A GPS receiver 4, which receives GPS signals from satellites through an antenna 5, is connected to the microcomputer 1C, which can conclude the position of one's car based on the GPS signals (GPS navigation).

[0252] A DVD drive 6, which can capture map data or real image data from a DVD-ROM 17C (other storage devices are also allowed) in which the map data and the real image data of satellite photographs showing the earth's surface, formed on the same scale as the map data are recorded, is connected to the microcomputer 1C, which based on the concluded one's car current position information, route information regarding the below-described guidance route and the like, stores the map data (particularly, the below-described road data, facility data and the like) and the real image data required from the DVD-ROM 17C in a RAM la within the microcomputer 1C. Here, as a method for allowing the real image data to correspond to the position coordinates, a method wherein the latitudes and longitudes of the upper left and lower right points of the rectangular area shown by the real image data are used is exemplified.

[0253] The map data comprises road data, facility data and the like, and the road data comprises node data and link data. As attached data to the node data, there are coordinates, node IDs and connection information, while as attached data to the link data, there are node IDs of both ends, road configurations (coordinates of interpolated points), road types and widths

[0254]FIG. 19 is an illustration for descriptions of the relationship among nodes, links, and the interpolated points. As shown in FIG. 19, the nodes are intersections at which a road and another road cross each other, the links are segments through which the node or the interpolated point, and the node or the interpolated point are connected, and the interpolated points are points for expressing the shape of the link.

[0255] As shown in FIG. 20, the facility data comprises classifications of facilities (such as school, convenience store, bank and park), address coordinates showing addresses thereof and space information showing the spaces thereof.

[0256]FIG. 21 is an illustration for descriptions of the address coordinates and the space information, which shows that space information of a facility A comprises the coordinates of four points, (x₁₁, y₁₁)-(x₁₄, y₁₄), and that space information of a facility B comprises the coordinates of five points, (x₂₁, y₂₁)-(x₂₅, y₂₅). And it also shows that the address coordinates of the facility A are (x₁₀, y₁₀), and that the address coordinates of the facility B are (x₂₀, y₂₀)

[0257] By conducting the map-matching wherein the concluded one's car current position and the map data (the real image data) are matched, the microcomputer 1C can display a map image (a real image) in which the one's car current position is precisely shown on a display panel 9 b.

[0258] And switch signals output from a joystick 8 a or button switches 8 b arranged on a remote control 8, or switch signals output from button switches 9 a arranged on a monitor 9 are input to the microcomputer 1C, in which the processing corresponding to these switch signals is conducted. For example, when the microcomputer 1C captures information of a goal, transit points and the like from these switches, it finds an optimum route from the one's car current position (starting point) to the goal via the transit points and displays that as a guidance route with a map picture on the display panel 9 b.

[0259] At the top, bottom and both sides of the display panel 9 b, multiple infrared LEDs and multiple phototransistors are arranged in the opposed positions to each other, so that the locations where a finger touched the display panel 9 b can be detected. The detected results can be acquired by the microcomputer 1C.

[0260] The processing operation {circle over (1)} performed by the microcomputer 1C in the navigation system in which the image display according to the embodiment (8) is adopted is described below by reference to a flow chart shown in FIG. 22. First, the current position of one's car is computed from the GPS signals and the like (Step 131), and based on the computed one's car current position information and the map data (particularly road data), a map image showing the periphery of the one's car current position is displayed on the display panel 9 b (Step 132).

[0261] Following that, whether or not facilities entered as the facility data exist on the map image appearing on the display panel 9 b is judged (Step 133). When it is judged that appropriate facilities exist, or that facilities to be displayed on the map image (such as a school P₁, a park P₂ and a ballpark P₃ shown in the below-described FIG. 23) exist, real image data corresponding to real images showing the facilities is read from a RAM 1 a based on space information showing the spaces of the appropriate facilities (Step 134), and then, real images corresponding to the read real image data are displayed in the spaces to be displayed on the map image (or the spaces shown by the space information) (Step 135). On the other hand, when it is judged that no appropriate facility exists in Step 133, the processing operation {circle over (1)} is ended at once.

[0262]FIG. 23 is an illustration showing a state where real images showing a school and the like are displayed on a map image appearing on the display panel 9 b, wherein M represents a one's car position mark, and P₁-P₃ represent real images showing a school, a park and a ballpark, respectively.

[0263] Using the navigation system in which the image display according to the embodiment (8) is adopted, in the spaces of facilities (facilities such as a school, a park and a ballpark) on the map image appearing on the display panel 9 b, the real images showing the facilities on the same scale as the map image are displayed.

[0264] Therefore, the facilities displayed on the map image are real images, as a matter of course, and the sizes (plot areas) thereof are also displayed similarly to the actual ones, so that it can be made very easy to grasp the situation shown by the map image.

[0265] A navigation system in which an image display according to an embodiment (9) is adopted is described below. Here, since the construction of the navigation system is similar to that of the navigation system shown in FIG. 12 except for the microcomputer 1C, a microcomputer is marked differently and others are not described below.

[0266] The processing operation {circle over (2)} performed by the microcomputer 1D in the navigation system in which the image display according to the embodiment (9) is adopted is described below by reference to a flow chart shown in FIG. 24. First, the current position of one's car is computed from the GPS signals and the like (Step 141), and based on the computed one's car current position information and the map data (particularly road data), a map image showing the periphery of the one's car current position is displayed on a display panel 9 b (Step 142).

[0267] Following that, whether or not facilities entered as the facility data exist on the map image appearing on the display panel 9 b is judged (Step 143). When it is judged that appropriate facilities exist, or that facilities to be displayed on the map image (such as a school P₁, a park P₂ and a ballpark P₃ shown in the below-described FIG. 25) exist, blocks (e.g. ranges partitioned by relatively wide roads such as principal roads, blocks E₁-E₃ shown in FIG. 25) in which the facilities are included are obtained based on address coordinates showing the addresses of the appropriate facilities and road data (Step 144). Here, as a method for obtaining the blocks, a method wherein the coordinates of nodes showing the ranges and the coordinates of interpolated points are picked out is exemplified.

[0268] Then, real image data corresponding to real images showing the blocks in which the facilities are included is read from a RAM 1 a based on the block space information (such as the coordinates of the nodes and the coordinates of the interpolated points, which show the ranges) (Step 145), and then, real images corresponding to the read real image data are displayed in the spaces to be displayed on the map (or the spaces shown by the space information) (Step 146). On the other hand, when it is judged that no appropriate facility exists in Step 143, the processing operation {circle over (2)} is ended at once.

[0269]FIG. 25 is an illustration showing a state where real images showing blocks in which facilities such as a school are included are displayed on a map image appearing on the display panel 9 b, wherein M represents a one's car position mark, and P₁-P₃ represent real images showing a school, a park and a ballpark, respectively. And E₁-E₃ therein represent real images showing blocks in which the school P₁, park P₂ and ballpark P₃ are included, respectively.

[0270] Using the navigation system in which the image display according to the embodiment (9) is adopted, in the spaces of blocks (the ranges of a school and the like enclosed by relatively wide roads such as principal roads) in which facilities (facilities such as a school, a park and a ballpark) are included on the map image appearing on the display panel 9 b, the real images showing the blocks on the same scale as the map image are displayed.

[0271] Therefore, the facilities displayed on the map image are real images, as a matter of course, and the sizes (plot areas) thereof are also displayed similarly to the actual ones, so that it can be made very easy to grasp the situation shown by the map image. In addition, since not only the facilities but also the blocks in which the facilities are included are displayed using real images, it is possible to let the user know the actual situation of not only the facilities but also the surroundings thereof.

[0272] In the case of displaying a real image which looks as if only the facility were cut out on the map image, as shown in FIG. 23, space information (or two-dimensional information) showing the space (or plane) of a facility such as a school is required as the facility data. However, in the case of displaying a real image showing a block in which the facility is included, only address information showing the address (or point) of a facility such as a school is needed. Therefore, the image display according to the embodiment (9) has an advantage that the preparation of not the space information of a high level but the address information of a relatively low level is only required.

[0273] A navigation system in which an image display according to an embodiment (10) is adopted is described below. Here, since the construction of the navigation system is similar to that of the navigation system shown in FIG. 12 except for the microcomputer 1C, a microcomputer is marked differently and others are not described below.

[0274] The processing operation {circle over (3)} performed by the microcomputer 1E in the navigation system in which the image display according to the embodiment (10) is adopted is described below by reference to a flow chart shown in FIG. 26(a). First, the current position of one's car is computed from the GPS signals and the like (Step 151), and based on the computed one's car current position information and the map data (particularly road data), a map image showing the periphery of the one's car current position is displayed on a display panel 9 b (Step 152).

[0275] Following that, whether or not facilities entered as the facility data exist on the map image appearing on the display panel 9 b is judged (Step 153). When it is judged that appropriate facilities exist, or that facilities to be displayed on the map image (such as a school P₁, a park P₂ and a ballpark P₃ shown in the below-described FIG. 27) exist, real image data corresponding to real images showing the facilities or real images showing blocks is read from a RAM 1 a based on space information showing the spaces of the appropriate facilities or space information showing the spaces of the blocks in which the facilities are included (Step 154). And then, real images corresponding to the read real image data are displayed in the spaces to be displayed on the map image (or the spaces shown by the space information) (Step 155). On the other hand, when it is judged that no appropriate facility exists in Step 153, the processing operation {circle over (3)} is ended at once.

[0276] The processing operation in Step 154 is described below in more detail by reference to a flow chart shown in FIG. 26(b). Here, the processing operation is conducted on each facility that should be displayed on the map image.

[0277] First, whether the facility should be displayed by block display or not is judged (Step 154 a). Here, the judgment of whether the facility should be displayed by block display is conducted based on the class of the facility, the size thereof and the like. For example, concerning a facility such as a school or a ballpark whose boundary is relatively clear, a real image showing only the facility is displayed, while concerning a facility such as a park whose boundary is relatively obscure, a real image showing a block in which the facility is included is displayed.

[0278] When it is judged that the facility is not a facility to be displayed by block display in Step 154 a, real image data corresponding to a real image showing the facility is read from the RAM 1 a, based on space information showing the space of the appropriate facility (such as a school P₁ or a ballpark P₃ shown in FIG. 27) (Step 154 b).

[0279] On the other hand, when it is judged that the facility is a facility to be displayed by block display, a block (e.g. a range partitioned by relatively wide roads such as principal roads, a block E₂ shown in FIG. 27) in which the facility is included is obtained based on address coordinates showing the address of the facility (e.g. a park P₂ shown in FIG. 27) and road data (Step 154 c). Then, based on the block space information (such as the coordinates of the nodes and the coordinates of the interpolated points, which show the range), real image data corresponding to a real image showing the block in which the facility is included is read from the RAM 1 a (Step 154 d).

[0280]FIG. 27 is an illustration showing a state where real images showing facilities such as a school and a block in which a park is included are displayed on a map image appearing on the display panel 9 b, wherein M represents a one's car position mark, and P₁-P₃ represent real images showing a school, a park and a ballpark, respectively. And E₂ therein represents a real image showing a block in which the park P₂ is included.

[0281] The navigation system in which the image display according to the embodiment (10) is adopted has a function of displaying the real image showing a facility on the same scale as the map image in the space of the facility on the map image appearing on the display panel 9 b, and a function of displaying the real image showing a block in which the facility is included on the same scale as the map image in the space of the block including the facility on the map image, and moreover, these functions are properly used depending on a predetermined condition. Therefore, since the displays of real images are properly conducted depending on the condition, a more useful display mode can be realized.

[0282] Here, in the navigation systems in which the image displays according to the embodiments (8)-(10) are adopted, all of the facilities entered as the facility data are displayed using real images, but in a navigation system in which an image display according to another embodiment is adopted, the user may be able to carry out various types of setting through a screen appearing on the display panel 9 b. For example, through the “FACILITY CLASS SELECTION” screen as shown in FIG. 28, the user may be able to select the class of facilities whose real images such as satellite photographs are displayed, and the microcomputers 1C, 1D and 1E may conduct the display control of real images according to the user's command selected through the “FACILITY CLASS SELECTION” screen.

[0283] In addition, in a navigation system in which an image display according to still another embodiment is adopted, the user may be able to carry out the setting of a real image display concerning not a class of a facility but a specific facility (such as the name or address of a facility), or by storing the past driving record data in a nonvolatile memory (not shown) so as to find facilities which the user had ever visited based on the driving record data, the facilities may be regarded as facilities to be displayed as the real images.

[0284] A navigation system in which an image display according to an embodiment (11) is adopted is described below. Here, since the construction of the navigation system is similar to that of the navigation system shown in FIG. 12 except for the microcomputer 1C, a microcomputer is marked differently and others are not described below.

[0285] The processing operation {circle over (4)} performed by the microcomputer 1F in the navigation system in which the image display according to the embodiment (11) is adopted is described below by reference to a flow chart shown in FIG. 29. First, the current position of one's car is computed from the GPS signals and the like (Step 161), and based on the computed one's car current position information and the map data (particularly road data), a map image showing the periphery of the one's car current position is displayed on a display panel 9 b (Step 162).

[0286] Following that, the map image appearing on the display panel 9 b is partitioned into a certain number of regions according to a predetermined condition to form blocks (Step 163). Here, as a method for forming the blocks, a method wherein several blocks are formed along relatively wide roads such as principal roads based on the road data is exemplified. The regions of the formed blocks can be expressed with the coordinates of nodes and the coordinates of interpolated points. FIG. 30 is an illustration for descriptions of a state where a map image appearing on the display panel 9 b is partitioned into a certain number of regions, wherein E_(a)-E_(n) each represent a region of each block.

[0287] Then, whether or not blocks including facilities (e.g. a school, a park and a ballpark) entered as the facility data exist is judged (Step 164). When it is judged that appropriate blocks (such as blocks E_(a), E_(j) and E_(n) shown in the below-described FIG. 31) exist, real image data corresponding to real images showing the blocks in which the facilities are included is read from a RAM 1 a based on space information of the blocks (Step 165). And then, real images corresponding to the read real image data are displayed in the spaces to be displayed on the map image (or the spaces shown by the space information) (Step 166). On the other hand, when it is judged that no appropriate block exists in Step 164, the processing operation {circle over (4)} is ended at once.

[0288]FIG. 31 is an illustration showing a state where real images showing blocks in which facilities such as a school are included are displayed on a map image appearing on the display panel 9 b, wherein M represents a one's car position mark, and P₁-P₃ represent real images showing a school, a park and a ballpark, respectively. And E_(a), E_(j) and E_(n) each therein represent a real image of a block in which the school P₁, park P₂ or ballpark P₃ is included.

[0289] Using the navigation system in which the image display according to the embodiment (11) is adopted, in the spaces of blocks (e.g. ranges of a school and the like partitioned by relatively wide roads such as principal roads) including the facilities to be displayed among the blocks formed on the map image appearing on the display panel 9 b, the real images showing the blocks on the same scale as the map image are displayed.

[0290] That is, the real images are displayed as if they were fitted in the spaces of blocks including the facilities to be displayed, which makes it possible to considerably easily grasp the situation shown by the map image.

[0291] Here, in the navigation system in which the image display according to the embodiment (11) is adopted, all of the blocks including facilities entered as the facility data are displayed using real images, but in a navigation system in which an image display according to another embodiment is adopted, the user may be able to carry out various types of setting through a screen appearing on the display panel 9 b. For example, through the “FACILITY CLASS SELECTION” screen (see FIG. 28), the user may be able to select the class of facilities whose real images such as satellite photographs are displayed, and the microcomputer 1F may conduct the display control of real images according to the user's command selected through the “FACILITY CLASS SELECTION” screen.

[0292] In addition, in a navigation system in which an image display according to still another embodiment is adopted, the user may be able to carry out the setting of a real image display concerning not a class of a facility but a specific facility or zone, or by storing the past driving record data in a nonvolatile memory (not shown) so as to find facilities or zones to which the user has ever been based on the driving record data, the blocks including the facilities or zones to which the user has ever been may be displayed with the real images.

[0293] A navigation system in which an image display according to an embodiment (12) is adopted is described below. Here, since the construction of the navigation system is similar to that of the navigation system shown in FIG. 12 except for the microcomputer 1C, a microcomputer is marked differently and others are not described below.

[0294] The processing operation {circle over (5)} performed by the microcomputer 1G in the navigation system in which the image display according to the embodiment (12) is adopted is described below by reference to a flow chart shown in FIG. 32. First, the current position of one's car is computed from the GPS signals and the like (Step 171), and whether or not facilities entered as the facility data exist in the area around the one's car position to be displayed on the display panel 9 b is judged (Step 172).

[0295] When it is judged that appropriate facilities (such as a school P₁, a park P₂ and a ballpark P₃ shown in the below-described FIG. 33) exist therein, blocks (e.g. ranges partitioned by relatively wide roads such as principal roads, blocks E₁-E₃ shown in FIG. 33) in which the facilities are included are obtained based on address coordinates showing the addresses of the appropriate facilities and road data (Step 173). Here, as a method for obtaining the blocks, a method wherein the coordinates of nodes and the coordinates of interpolated points, which show the ranges are picked out is exemplified.

[0296] Then, based on the one's car current position information computed in Step 171 and the real image data stored in a RAM 1 a, a real image showing the periphery of the one's car current position is displayed on the display panel 9 b (Step 174). Here, based on space information of the blocks (such as the coordinates of the nodes and the coordinates of the interpolated points, which show the ranges), the blocks in which the facilities are included (e.g. blocks E₁-E₃) are displayed with color real images, while the other portion is displayed with a monochrome real image, leading to differentiation of both of them.

[0297] When it is judged that no appropriate facility exists in Step 172, the differentiation of display is not required. Therefore, based on the one's car current position information computed in Step 171 and the real image data stored in the RAM 1 a, a real image showing the periphery of the one's car current position is displayed by monochrome on the display panel 9 b (Step 175).

[0298]FIG. 33 is an illustration showing a state where real images are displayed on the display panel 9 b, wherein M represents a one's car position mark, and P₁-P₃ represent real images showing a school, a park and a ballpark, respectively. And E₁-E₃ each therein represent a real image of a block in which the school P₁, park P₂ or ballpark P₃ is included.

[0299] Using the navigation system in which the image display according to the embodiment (12) is adopted, when the real images are displayed on the display panel 9 b, with differentiating blocks including the facilities entered as the facility data (color display) from the other portion (monochrome display), the real images are displayed.

[0300] Therefore, the user can know blocks to which more attention should be paid or the like in an instant, resulting in realization of a considerably useful unit.

[0301] Here, in the navigation system in which the image display according to the embodiment (12) is adopted, the blocks including facilities entered as the facility data and the other blocks are differentiated, but in a navigation system in which an image display according to another embodiment is adopted, the user may be able to carry out various types of setting through a screen appearing on the display panel 9 b. For example, through the “FACILITY CLASS SELECTION” screen (see FIG. 28), the user may be able to select the class of facilities whose real images such as satellite photographs are displayed, and the microcomputer 1G may differentiate the blocks including the facilities selected through the “FACILITY CLASS SELECTION” screen from the other blocks.

[0302] In addition, in a navigation system in which an image display according to still another embodiment is adopted, the user may be able to carry out the setting of a real image display concerning not a class of a facility but a specific facility, or by storing the past driving record data in a nonvolatile memory (not shown) so as to find facilities or zones to which the user has ever been based on the driving record data, the blocks including the facilities or zones to which the user has ever been and the other blocks may be differentiated. Thus, through the contents appearing on the display panel 9 b, the user can know which area the user has ever visited in an instant.

[0303] In the image displays according to the embodiments (8)-(12), only cases where real images showing prescribed facilities (such as a school, a park and a ballpark) or real images showing blocks including the prescribed facilities are displayed are described, but real images shown by the image display according to the present invention are not limited to the prescribed facilities. Real images showing prescribed places or real images showing blocks including the prescribed places are displayed thereby. For example, real images showing rice fields, fields, irrigation ponds and the like, or blocks including rice fields, fields, irrigation ponds and the like may be displayed. 

What is claimed is:
 1. An image display, which has: a first photo picture preparing device to prepare a photo picture on a prescribed reduced scale, based on photo data read from a first photo data storage device in which photo data showing the surface of the earth is stored; and a first photo picture display device to display a photo picture on the prescribed reduced scale which is prepared by the first photo picture preparing device; comprising: a second photo picture preparing device to prepare a photo picture on another reduced scale different from the prescribed reduced scale based on the photo data; and a first display switching device to conduct display switching to a photo picture on the another reduced scale which is prepared by the second photo picture preparing device with a user's command to switch the reduced scale; wherein the first and second photo picture preparing devices prepare the photo pictures without enlargement.
 2. An image display, which has: a third photo picture preparing device to prepare a photo picture on a prescribed reduced scale, based on photo data on a prescribed scale read from a second photo data storage device in which photo data of two or more types on different scales to one area is stored; and a second photo picture display device to display a photo picture on the prescribed reduced scale which is prepared by the third photo picture preparing device; comprising: a fourth photo picture preparing device to prepare a photo picture on another reduced scale different from the prescribed reduced scale, based on photo data on another scale different from the prescribed scale read from the second photo data storage device; and a second display switching device to conduct display switching to a photo picture on the another reduced scale which is prepared by the fourth photo picture preparing device with a user's command to switch the reduced scale.
 3. An image display, which has: a first map picture preparing device to prepare a map picture based on map data read from a map data storage device in which map data is stored; and a first map picture display device to display a map picture which is prepared by the first map picture preparing device; comprising: a fifth photo picture preparing device to prepare a photo picture showing the periphery of the current position of one's own, based on photo data regarding the periphery of the one's current position read based on the one's current position information from a third photo data storage device in which photo data showing the surface of the earth covering limited areas is stored; a first one's position judging device to judge whether the one is within the areas based on the one's current position information; and a third photo picture display device to display a photo picture showing the periphery of the one's current position which is prepared by the fifth photo picture preparing device, when the first one's position judging device judges the one to be within the areas.
 4. An image display, which has: a first map picture preparing device to prepare a map picture based on map data read from a map data storage device in which map data is stored; and a first map picture display device to display a map picture which is prepared by the first map picture preparing device; comprising a fifth photo picture preparing device to prepare a photo picture showing the periphery of the current position of one's own, based on photo data regarding the periphery of the one's current position read based on the one's current position information from a third photo data storage device in which photo data showing the surface of the earth covering limited areas is stored; a first one's position judging device to judge whether the one is within the areas based on the one's current position information; and a fourth photo picture display device to display a photo picture showing the periphery of the one's current position which is prepared by the fifth photo picture preparing device, with a user's command to display the photo picture while the one has been judged to be within the areas by the first one's position judging device.
 5. An image display, which has: a first map picture preparing device to prepare a map picture based on map data read from a map data storage device in which map data is stored; and a first map picture display device to display a map picture which is prepared by the first map picture preparing device; comprising: a fifth photo picture preparing device to prepare a photo picture showing the periphery of the current position of one's own, based on photo data regarding the periphery of the one's current position read based on the one's current position information from a third photo data storage device in which photo data showing the surface of the earth covering limited areas is stored; a first one's position judging device to judge whether the one is within the areas based on the one's current position information; a first switch forming device to form a command switch for giving a command to display the photo picture, when the first one's position judging device judges the one to be within the areas; and a fifth photo picture display device to display a photo picture showing the periphery of the one's current position which is prepared by the fifth photo picture preparing device, when the command switch is turned on by a user.
 6. An image display, comprising: a sixth photo picture preparing device to prepare photo pictures showing prescribed spots, based on photo data regarding the prescribed spots existing on a guidance route or around the guidance route read based on the guidance route information from a first photo data storage device in which photo data showing the surface of the earth is stored; and a sixth photo picture display device to display a photo picture showing the prescribed spot which is prepared by the sixth photo picture preparing device.
 7. An image display, comprising: a seventh photo picture preparing device to prepare a photo picture based on photo data read from a first photo data storage device in which photo data showing the surface of the earth is stored; a seventh photo picture display device to display a photo picture which is prepared by the seventh photo picture preparing device; and a detailed information providing device to provide detailed information regarding spots to a user, based on detailed data related to the spots existing within the area shown in the photo picture read from a detailed data storage device in which detailed data related to prescribed spots is stored.
 8. An image display, comprising: an eighth photo picture preparing device to prepare a photo picture showing the periphery of a goal, based on photo data regarding the periphery of the goal read based on the goal position information from a first photo data storage device in which photo data showing the surface of the earth is stored; and an eighth photo picture display device to display the photo picture showing the periphery of the goal prepared by the eighth photo picture preparing device.
 9. An image display according to claim 8, wherein the eighth photo picture display device displays the photo picture showing the periphery of the goal when the goal is selected by a user.
 10. An image display according to claim 8, comprising: a second one's position judging device to judge whether one reaches close to the goal based on the one's current position information and the goal position information; wherein the eighth photo picture display device displays the photo picture showing the periphery of the goal when the second one's position judging device judges the one to have reached close to the goal.
 11. An image display, which has: a first map picture preparing device to prepare a map picture based on map data read from a map data storage device in which map data is stored; and a first map picture display device to display a map picture which is prepared by the first map picture preparing device; comprising: a seventh photo picture preparing device to prepare a photo picture based on photo data read from a first photo data storage device in which photo data showing the surface of the earth is stored; and a third display switching device to conduct display switching from the map picture to the photo picture and/or from the photo picture to the map picture with matching the area shown by the map picture with the area shown by the photo picture.
 12. An image display, which has: a ninth photo picture preparing device to prepare a photo picture showing the periphery of the one's current position, based on photo data related to the periphery of the one's current position read based on the one's current position information from a first photo data storage device in which photo data showing the surface of the earth is stored; a ninth photo picture display device to display a photo picture showing the periphery of the one's current position which is prepared by the ninth photo picture preparing device; and a first current position display device to show the one's current position on the photo picture based on the one's current position information; comprising: a second map picture preparing device to prepare a map picture based on map data read from a map data storage device in which map data is stored; and a fourth display switching device to conduct step-by-step display switching from the photo picture to the map picture according to the one's travel, by making the display area of the photo picture smaller, while making the display area of the map picture larger based on the one's current position information.
 13. An image display, comprising: a tenth photo picture preparing device to prepare a photo picture, based on photo data read based on a predetermined condition from a fourth photo data storage device in which photo data taken in two or more different states to one area is stored; and a tenth photo picture display device to display a photo picture which is prepared by the tenth photo picture preparing device.
 14. An image display, which has: a first map picture preparing device to prepare a map picture based on map data read from a map data storage device in which map data is stored; and a first map picture display device to display a map picture which is prepared by the first map picture preparing device; comprising: a seventh photo picture preparing device to prepare a photo picture based on photo data read from a first photo data storage device in which photo data showing the surface of the earth is stored; and a multi-screen display device to display a map picture which is prepared by the first map picture preparing device and a photo picture which is prepared by the seventh photo picture preparing device on the same display screen.
 15. An image display, comprising: a seventh photo picture preparing device to prepare a photo picture based on photo data read from a first photo data storage device in which photo data showing the surface of the earth is stored; and a seventh photo picture display device to display a photo picture which is prepared by the seventh photo picture preparing device; wherein the seventh photo picture preparing device prepares a photo picture on which prescribed image processing is conducted based on a predetermined condition.
 16. An image display, which has: a display control device to display a map image and a real image on the same scale concerning the same area on a display screen based on map data and real image data; wherein the display control device has a function of composing the map image and the real image so that in the background of either of the map image and the real image, the other image is overlaid in a given region, and only the other image can be seen in the composite region.
 17. An image display, which has: a display control device to display a map image and a real image on the same scale concerning the same area on a display screen based on map data and real image data; wherein the display control device has a function of composing the map image and the real image so that in the background of either of the map image and the real image, the other image is overlaid in a given region, and through either of the map image and the real image, the other image can be seen in the whole or part of the composite region.
 18. An image display according to claim 17, comprising: a composition level setting device which enables the setting of the composition level of the images; wherein the display control device composes the images based on the composition level set by the composition level setting device concerning the composite region.
 19. An image display according to claim 17, wherein the display control device composes the images so that the display brightness of a background image becomes higher from the composite region toward the outside of the region.
 20. An image display according to claim 16, which is adopted in a navigation system that can guide oneself to a goal by providing information such as routes and maps required for reaching the goal to a user, wherein the given region is any of: a peripheral area of the one's own obtained based on the one's position information; a peripheral area of the goal obtained based on the goal position information; a peripheral area of a preset facility obtained based on the preset facility position information; and a peripheral area of a preselected position obtained based on position information of the preselected position previously pointed by the user.
 21. An image display according to claim 16, which is adopted in a navigation system that can guide oneself to a goal by providing information such as routes and maps required for reaching the goal to a user; wherein the given region is an almost upper half region or an almost lower half region on the display screen.
 22. An image display according to claim 16, which is adopted in a navigation system that can guide oneself to a goal by providing information such as routes and maps required for reaching the goal to a user; wherein the given region is a peripheral area of the route obtained based on route information regarding the route.
 23. An image display, which has a first display control device to display a map image based on map data on a display screen, comprising: a second display control device to display real images showing prescribed places on the same scale as the map image in the spaces of the prescribed places on the map image, based on space information showing the spaces of the prescribed places on the map and real image data formed so as to be able to correspond to the position coordinates.
 24. An image display, which has a first display control device to display a map image based on map data on a display screen, comprising: a block computing device to find a block where a prescribed place is included based on address information showing the address of the prescribed place; and a third display control device to display a real image showing a block on the same scale as the map image in the space of the block on the map image, based on space information showing the space of the block computed by the block computing device and real image data formed so as to be able to correspond to the position coordinates.
 25. An image display, which has a first display control device to display a map image based on map data on a display screen, comprising: a second display control device to display a real image showing a prescribed place on the same scale as the map image in the space of the prescribed place on the map image, based on space information showing the space of the prescribed place on the map and real image data formed so as to be able to correspond to the position coordinates; a block computing device to find a block where the prescribed place is included based on address information showing the address of the prescribed place; a third display control device to display a real image showing a block on the same scale as the map image in the space of the block on the map image, based on space information showing the space of the block computed by the block computing device and the real image data; and a switching control device to control the proper use of the control by the second display control device and the control by the third display control device, depending on a predetermined condition.
 26. An image display according to claim 23, comprising: a place selection device which enables a selection of a specific place; wherein the prescribed place is the specific place selected by the place selection device.
 27. An image display according to claim 23, comprising: a usage selection device which enables a selection of a usage of a place; wherein the prescribed place is a place used for the usage selected by the usage selection device.
 28. An image display according to claim 23, which is adopted in a navigation system that can guide oneself to a goal by providing information such as routes and maps required for reaching the goal to a user, comprising: a storage device to store information regarding the past driving record of the one's own; and a place computing device to find a specific place based on the driving record stored in the storage device; wherein the prescribed place is a place computed by the place computing device.
 29. An image display, which has a first display control device to display a map image based on map data on a display screen, comprising: a fourth display control device to display a real image showing a prescribed block on the same scale as the map image in the space of the block on the map image, based on space information showing the space of the prescribed block and real image data formed so as to be able to correspond to the position coordinates.
 30. An image display according to claim 29, which is adopted in a navigation system that can guide oneself to a goal by providing information such as routes and maps required for reaching the goal to a user, comprising: a storage device to store information regarding the past driving record of the one's own; and a zone computing device to find a specific zone based on the driving record stored in the storage device; wherein the prescribed block is a block including a zone computed by the zone computing device.
 31. An image display, which has a fifth display control device to display a real image such as a satellite photograph or an air photograph showing the surface of the earth on a display screen, based on real image data formed so as to be able to correspond to the position coordinates; wherein the fifth display control device differentiates a prescribed block from the other portion to display the real image, based on space information showing the space of the prescribed block and the real image data.
 32. An image display according to claim 31, comprising: a block selection device which enables a selection of a specific block; wherein the prescribed block is the specific block selected by the block selection device.
 33. An image display according to claim 31, which is adopted in a navigation system that can guide oneself to a goal by providing information such as routes and maps required for reaching the goal to a user, comprising: a storage device to store information regarding the past driving record of the one's own; and a zone computing device to find a specific zone based on the driving record stored in the storage device; wherein the prescribed block is a block including a zone computed by the zone computing device.
 34. An image display, which has a fifth display control device to display a real image such as a satellite photograph or an air photograph showing the surface of the earth on a display screen, based on real image data formed so as to be able to correspond to the position coordinates; wherein the fifth display control device displays a real image such as a satellite photograph or an air photograph showing a specific area based on information showing the specific area such as a park or a facility.
 35. An image display, which has a sixth display control device to display a real image such as a satellite photograph or an air photograph showing the periphery of a specific position on a display screen, based on real image data formed so as to be able to correspond to the position coordinates and position information of the specific position such as one's position; comprising a specific position display device to show the specific position on a real image appearing on the display screen. 